7) The Shu”t Ein Yitzchok (Vol. 1, Even HaEzer, siman 70, anaf 2) writes that certainly her husband doesn’t need to go with, as only by a talmid do we find that the rebbe must go with, and not by anyone else.
The Tzofnas Paneach (Makkos 10a) is in doubt about this. He writes there is a big difference between a husband and a rebbe, as a rebbe who taught Torah to a bad talmid is negligent and he should have picked better talmidim. However, when it comes to a husband, we can’t say this, therefore, perhaps he is exempt. On the other hand, a husband is worse, as every second he could have divorced his wife and he didn’t, whereas for a rebbe to get rid of his talmid is not so simple.
According to the reasoning of the Rambam mentioned above, וחיי בעלי חכמה ומבקשיה בלא תלמוד כמיתה חשובין, this would only apply to a talmid and not to a wife.
