SO I think I found a work around.
First I tried to go in and just delete the research subject files for the the galaxy travel techs. That caused a minidump on trying to load the mod....
I thenm tried to just up the cost of the research until it was prohibitively expensive. This looked like it would work, but I also wanted to make the workhole travel easy to get.
So I just changed the effect of the gaxaly travel tech to "allowswormholetravel" from "allowsgalaxytravel" in the reserch subject listing. it still says the same stuff, but it doesn't let you travel star to star and does let you travel through worm holes.
Eh, it's not perfect, but it works.
This also leaves the artifact that lets you travel from galaxy to galaxy intact, so one lucky race WILL be able to travel star to star...