Yes, the teensy will work with that board, the terminal 102 key board like yours has the same kind of internal component placement as the larger M122 boards, you have room in there for the bulkhead connector, and also the teensy. You do have to shave some of the plastic off of the back of the bulkhead connector where it touches the bottom of the metal plate inside, but not hard at all to do.
I also offer a conversion service if you don't want to attempt it yourself.