The specimen AMNH 2550-2553 you mention was originally assigned to the ornithomimosaur Coelosaurus antiquus by Leidy (1865), only to be later made the holotype of the new species Laelaps macropus by Cope (1868), who distinguished it from Dryptosaurus by its more gracile toes. Matthew and Brown (1922) referred the Laelaps macropus holotype back to Coelosaurus, unaware of the differences between Coelosaurus and L. macropus jotted out by Cope (1870), while Holtz (2004) tabulated L. macropus as a dubious tyrannosauroid. Yun (2017) has confirmed the tyrannosauroid nature of Laelaps macropus and its distinctness from Dryptosaurus and erected the new genus Teihivenator for L. macropus. Thus, the paper should reflect that AMNH 2550-2553 was originally described as Laelaps macropus and is now called Teihivenator. Sebastian Dalman told me by email back in 2015 that he is describing the Merchantville tyrannosaur specimen as a new species, and that a Cenomanian-age tyrannosaur from the Potomac Formation of New Jersey is under description (see http://theropoddatabase.com/Tyrannosauroidea.html). Consequently, tyrannosaurs from Appalachia are represented by Appalachiosaurus, Dryptosaurus, and Teihivenator plus the Merchantville taxon (YPM VPPU.021795) and the Potomac Formation specimen, and you might also want to check indeterminate tyrannosaur specimens from Coniacian-late Campanian deposits in Alabama, Mississippi, Georgia, North Carolina, South Carolina, and Delaware (see http://theropoddatabase.com/Tyrannosauroidea.html) to see how those specimens compare to YPM VPPU.021795, Appalachiosaurus, Dryptosaurus, and Teihivenator.
Cope, E.D., 1868. On the genus Laelaps, American Journal of Science 2: 415-417.
Cope, 1870. Synopsis of the extinct Batrachia, Reptilia and Aves of North America. Transactions of the American Philosophical Society. 14, 1-252.
Holtz, 2004. Tyrannosauroidea. In Weishampel, Dodson and Osmolska (eds). The Dinosauria (second edition). University of California Press, Berkeley. 111-136.
Leidy, 1865. Memoir of the extinct reptiles of the Cretaceous formations of the United States. Smithsonian Contributions to Knowledge. 14, 1-135.
Matthew and Brown, 1922. The family Deinodontidae, with notice of a new genus from the Cretaceous of Alberta. Bulletin of the American Museum of Natural History. 46(6), 367-385.
Chan-gyu Yun, 2017. Teihivenator gen. nov., a new generic name for the tyrannosauroid dinosaur "Laelaps" macropus (Cope, 1868; preoccupied by Koch, 1836). Journal of Zoological And Bioscience Research. 4 (2): 7–13. doi:10.24896/jzbr.2017422.