I don’t think time works at quite the same speed between universes. It doesn’t in most other works of fiction in which characters trravel between universes. Also, in The Return, when Rumpel was talking to August (who was pretending to be Bae), he said that Bae had “crossed the barriers of time and space”. So, I would imagine that Rumpel would have made the curse take them to whatever time period Bae had landed in; then, the 28 years would have passed, so Bae would be about mid-30s. And, when he was talking to Archie earlier in the same episode, he mentioned that he didn’t know how old Bae was. So hopefully Baelfire is still very much alive in this world, otherwise that story would get very little closure.