I think (or thought) that the name(s) on the recorded deed and the name(s) on the ii membership needs to be the same. That is how my TS's have been recorded and enrolled in Interval.
But here is where is gets complicated but workable.... I make the reservations in II under my wife's login. (Long story but it was the result of software issues in Interval from a decade ago). So, ii gives me a Confirm with my wife's name first followed by mine. When we check in to the TS, I usually have to give them my wife's name. When we check in (like to a Marriott) I always check to make sure that they have MY Bonvoy number. Sometimes in Marriott.com (for Bonvoy), I'll add an upcoming trip (with my BV #) to my profile but I end up doing a search using my wife's name, OUR ii res number. It seems to work fine. So
@heckp, I'd suggest that you do an experiment - - go to Marriott.com (husband's acct) and try to enter your upcoming Marriott res # or your ii res #. When it errors out and cannot find that res, then do another search using YOUR name and res#. Maybe it'll work for you. It does for me....