I understand. A few of our workoholic characters we got around by saying that their bosses made them take a vacation, but Optimus Prime basically is the boss.

Another character came to the resort thinking that going to another universe might give him access to new and unfamiliar technology that might be useful to him, so the motive doesn't have to be vacation, but yeah, I understand how some characters are hard to get to willingly leave their canon friends and duties. In any case, if any way around that could be found, we'd love to have him and thank you for taking a look!