RailSounds 2 boards do work with TMCC, but two of the six versions have PICs that won't recognize the commands. You really don't want to use these -- they're really big, and all the connections are hard-wired, which makes them a pain to work with.
RailSounds 2.5 boards are also TMCC compatible, and I can only think of one PIC (from a RailSounds Christmas sound car) that doesn't recognize TMCC commands. These have all the usual Leoco/JST-EH connectors, are smaller in size, and much easier to work with. Most of the TMCC-equipped Geeps in the mid-1990s came with these boards before graduating to the modular RailSounds 3/4 system in 1998.
TRW