I don't know if there are any IM programs that wouldn't interview you without doing electives there. I was told (by upper years - no official sources) that McMaster and Toronto wouldn't interview those who didn't do elective with them, and I was offered interviews for both without having spent any elective time in any field for either (cancelled an elective at McMaster and didn't apply for one at Toronto). I ranked other programs higher so who knows if I would have gotten in, but not doing an elective there wasn't a barrier to getting interviewed at least.
Honestly, IM interviews can feel a bit random. Lots of examples of people having good electives/reference letters from places and not getting interviews there, despite being strong candidates and getting a lot of interviews elsewhere. I think there's a fair bit of luck involved with programs as large as IM where they have to sift through a huge amount of applications. I knew lots of strong candidates applying and interviewing everywhere was a rarity. (Although everyone seemed to end up where they wanted to end up).
If there is a school you're really interested in, I'd highly recommend trying to an elective there; it will help for future decision making and probably also help in the interview stage (what I felt were my best interviews were at schools I had spent time clinically and felt really strongly about the programs). But if you can't manage to schedule an elective somewhere you were hoping to end up, don't worry too much.