FWIW from my experience:
- Son went to a CAA school (mid-major, high academic) and also drafter after Jr year. That school routinely takes Juco transfers and walk ons. Stuff happens at schools....players don't make the grades, and/or "other stuff" happens where they can't play. (.....and the stories I could tell on the "other stuff")
- I also know of a CWS contender (actually, a CWS winner recently) that plucked players from the club team to fill in their roster when injury, "and other stuff" happened one season and they lost key players.
With that: contact the coaches at Michigan and ask for a tryout or when the walk-on tryouts will be in the fall, as well as gather info for their club team. Nick Schnabel is Michigan's recruiting coordinator/assistant coach. Send him your info now. Have your HS coach contact him as well, in your behalf. (I have personally met him when my son was going through the recruiting process.) https://mgoblue.com/staff.aspx?staff=487 They may not want to go on a limb to roster a player that may not be there the following year, but hey, if you make the team, you may not want to leave! Many/most players don't get to play baseball at their dream school (mine included) and Michigan IS a dream school for so many! Study VERY hard first semester because those are the college grades that you will send to PENN for consideration.
Someone mentioned the camp at Penn. It may be the best way to get in front of those coaches. Explain your situation to them ahead of attending.
Keep playing until someone tells you you can't. Club ball is still a good option.