And I'm the one who installed that DOS box doing the telescope control, also in 1995 - I must have been there just before you. We'd automated an almost identical telescope at Perth Observatory over 1989-1992 (the one used for this planet discovery), and when Mt John contacted us and asked for help, I went over and ported our code to their telescope, all in Turbo Pascal 6.0.
The communication technique - reading and writing shared files - was designed for a 'LANtastic' network under DOS in 1989. I knew we wouldn't be using DOS or LANtastic for long, and wanted something that was simple, and would transfer well to different systems.
Shortly afterwards we moved away from Turbo Pascal under DOS (to Virtual Pascal under OS/2 :-), and started using a MySQL server for communication - I think the New Zealand 61cm is still using the original DOS code, although the new 1.8m is a different deal entirely. Since 1998 or so, everything I've written has been in Python, and I don't miss the Pascal at all...
Andrew Williams (one of the authors on the planet discovery paper)