I think OP's point is that it's not GPIB, it's "GPIB", a.k.a. something that kind of looks like gpib if you squint, but really is some custom derivative that is only supported by one obscure piece of DOS-only software that doesn't work with more then 8MB of ram.

Those USB-GPIB tools work reasonably well for getting plots, but if you have an instrument that does weird things you're generally SOL.