Multiclip won’t accept sequences. It can use subclips though.
I’ve had situations where, with reel changes, one would like multiple reels from one camera as one angel. It can’t be done. You can subclip where the breaks are and create another multiclip so you can put two multiclips in a sequence.
Yea, the other alternative is to take the sequence, export, import to make it one clip. I agree, not very efficient.
Subclips do work though.