Definitely not, although contacts were indeed relatively rare. The most famous contact between the Yemenite community and the broader Jewish world in the Medieval Period is Moses Maimonides' Epistle to Yemen around 1172. It was greatly prized by the Yemenite community, and to this day the Yemenite Jewish communties base much of their practice directly on Maimonides' Mishneh Torah. This is in contrast to other communities who base their practice on the Shulchan Aruch (Sephardi) or the Rama's gloss on it (Ashkenazi).