For more detail - the tape drive in question (the original one) is an Interpreter TapeXchange external tape drive, which was a metal case with a nifty handle. Apparently they were popular. The power supply on the external housing was long dead, so I yanked the drive out - it was a Sankyo CP150SE. This drive also had some time-related issues and wasn't really able to read the tapes (it despooled one of them). So my friend was able to yank the data using another drive attached to a Linux host. In his investigation he saw the TXPLUS markings -- some sleuthing on the Internet shows that TXPLUS indeed was a software that came with this package. So despite the person sending me the drive, tapes, and TapeMate II, it may not be TapeMate unless TapeMate and TXPLUS are the same compression format.