When I run distcheck locally (not using Ubuntu though), the problem is vala cannot find vte. Maybe there is a separate package that vala needs to use vte?
The reason the `--disable-*` flags don't work is distcheck runs configure *after* whatever it's doing that's failing.
I'm going to try disabling multiterm in `Makefile.am`. The lines are just commented out, so if multiterm is ever fixed, the lines can be easily restored.