I don't see a reason why you couldn't (or why that should be rude or unfair). In the past I made my jam game and helped others out. There shouldn't be a problem the other way around.
Honestly the only thing that might cause an issue is the itch database. Idk if they set it up, so that one jammer can be linked to multiple projects. That is when you post a comment under a submission it makes a link to your game. Now I am curious if it allows you to do that and shows two games.
Probably you're going to have to be credited weirdly for your team game, so it works out.