Rafting to Madagascar? Yes for the hippos. No for the rest.

Elephant birds
The LRT links Aepyornis, the recently extinct elephant bird (Fig. 6), with Struthio, the ostrich. Both have a last common ancestor in Patagopteryx (80mya). Highly derived flightless geese (Asterorinis) are known from the latest Cretaceous. That means the much more primitive ratites had a much more primitive, Jurassic genesis, long before Gondwana split apart. This evidence indicates a continuous presence for large ratites on Madagascar without rafting in or walking in on a land bridge later than the K-T boundary.

Plesiorycteropus, the pseudo ‘aardvark‘
This taxon is known from a few partial fossils known since Fihol 1895 and described in detail by MacPhee 1994 (Fig. 7). Unfortunately MacPhee excluded many key taxa while discussing comparative anatomy, but did make comparisons to Talpa, the mole. In the LRT Plesiorycteropus nested with two other Madagascar taxa, the mongooses Crypotprocta and Eupleurus, not far from Herpestes the Eqyptian mongoose, Late Eocene Prohesperocyon, the pre-mole (not the earliest canid) and Talpa the extant mole, all within a subclade of the Carnivora. This basal placental clade had roots in the Early Jurassic. This phylogenetic evidence indicates a continuous presence for mongooses on Madagascar without rafting in or walking in on a land bridge later than the K-T boundary.

According to Masters, de Wit and Asher 2006
“by 83 million years, all of the major components we recognize today were separated by tracts of water. Madagascar’s fossil record and estimates of the timing of the extant vertebrate radiations in Madagascar are not easily reconciled with this history of fragmentation. Fossil faunas that lived prior to approx. 65 million years had a cosmopolitan flavour, but this was lost after the Cretaceous-Tertiary boundary.”

“Phylogenetic reconstructions of most extant Malagasy vertebrate radiations indicate divergence times that postdate the End-Cretaceous (lemurs, tenrecs, cichlid fish) and even the Early Miocene (chameleons, carnivores, rodents).”

“Most biogeographic explanations of these groups rely, therefore, on Simpson’s model of sweepstakes dispersal [Simpson 1940, 1951], but there are significant problems in applying the model to migrations from Africa to Madagascar, although its application is not so intractable between India and Madagascar. Alternative migration routes for consideration lie:

1. along the suite of fracture zones between Antarctica and Africa/Madagascar (known as the Antarctic-Africa Corridor), which may have been exposed episodically above sea level;
2. along a series of submerged basaltic ridges/plateaus with known or suspected continental crust between Antarctica and Africa/Madagascar/India flanking the Antarctic-Africa Corridor (e.g. the Madagascar Ridge, Mozambique Ridge, Conrad Plateau, Gunnerus Ridge);
3. between Africa and Madagascar along the Davie Ridge (parts of which are known to have been exposed episodically above sea level);
4. along the Deccan hotspot corridor between India and greater Africa.” (Fig. 8).

Masters, de Wit and Asher 2006 report the traditional story,
“The fossil records of the living mammalian orders begin at or shortly after the Cretaceous-Tertiary boundary [Alroy, 1999]. Hence the composition of Madagascar’s End-Cretaceous fauna is an important starting point for reconstructions of its biodiversity.”

As Masters, de Wit and Asher note, tradition holds that there is no continuity between pre K-T boundary Madagascar fauna and post K-T fauna but remains are extremely rare. Only one pre-K-T mammal, the derived paedothere marsupial Adalatherium, has been described.

By contrast, the LRT indicates that endemic Madagascar birds and mammals survived the K-T extinction event on the other side of the world.

Masters, de Wit and Asher continue,
“The lack of close relationships between the Upper Cretaceous fossils and the extant Malagasy vertebrates has led researchers to conclude that the basal stocks of the modern taxa must have arrived later by waif dispersal.”

According to the LRT, only the hippos rafted over, carried by First Century humans hoping to have hippo burgers in the years ahead. The rest of the taxa were Jurassic basal placentals and basal crown birds that survived the K-T extinction event on their island home close to the antipodes of the K-T crater. Fossils of these K-T survivors might show up someday on Madagascar, but for now the LRT provides the first phylogenetic and chronological evidence against the widely believed rafting hypothesis for most Madagascar vertebrates. If not, please provide a citation for that earlier hypothesis so I can promote it here.

PS
What about those Late Cretaceous dinosaurs? They all became extinct. Yes, they did and had a long time to do so if the K-T extinction event did not kill them.

References
Filhol H. 1894. Observations concernant quelques mammiferes fossiles nouveaux de
Quercy. Ann. Sci. Nat., Zool. Paleontol. (7e ser.) 16: 129-150.
Masters JC, de Wit MJ and Asher RJ 2006. Reconciling the Origins of Africa, India and Madagascar with Vertebrate Dispersal Scenarios. Folia Primatol 2006;77:399–418.
MacPhee RDE 1994. Morphology, Adaptations, and Relationships of Plesiorycteropus, and a Diagnosis of a New Order of Eutherian Mammals.” Bulletin of the American Museum of Natural History, 220 (1994): 1-214.
Reeves C 2014. The position of Madagascar within Gondwana and its movements during Gondwana dispersal. Journal of African Earth Sciences 94(2014):45–57.
Simpson GG 1940. Mammals and land bridges. Journal of the Washington Academy of Sciences 30:137–163.
Simpson GG 1951. Probabilities of dispersal in geologic time. Bulletin of the American Museum of Natural History 99: 163–176.

Reeves animation, breakup of Gondwana: http://www.reeves.nl

https://www.purdue.edu/newsroom/research/2010/100119HuberMadagascar.html

wiki/History_of_Madagascar
wiki/Malagasy_hippopotamus
wiki/Plesiorycteropus