Here are the limitations that I see:
Grossman is good. But he's not great. Not dynamic in any area. He has good plate discipline and gets on base... but only nominal power and not much BA. He's also 33 next year, so he's not on any upswing. His OBP, professionalism, bit-of-speed, and that he's a switch-hitter gives him PA's. But there are limitations in his profile.
Baddoo is dynamic. But struggles against lefties (.526 OPS versus .846 against righties), which suggests a platoon at this point, and is not as fluid in the field as you would think, nor has much of an arm for CF. Best in LF, but can cover CF if needed. Grossman should take 100% of his PA's against lefties at this point (.848 OPS against lefties versus .738 OPS against righties).
Hill is a dynamic centerfielder. But has trouble staying healthy. Not much BA, he does have a little pop in his bat but not enough for anyone to take notice. Very few PA's so far in MLB so he's unproven there. Same with on the basepaths... he has speed, but what's he going to do with it? In 139 AB's this year: .259 BA, 3 doubles 3 triples 3 HR's = .702 OPS. If he bumps that up to .750, and can stay healthy, that may = most of the CF PA's in 2022. If Hill sits some against tough righties and Baddoo takes those PA's, then Grossman can be the leftie bat in LF whilst Baddoo covers CF.
Greene is not coming up to MLB to be a 4th OF'er. Who the heck suggested that? If he comes up, he's a 90-95% starter. Maybe he gets some days off and Grossman plays instead... but 9 out of 10 games Greene is starting. IF Hill can hold onto CF, Greene is the starter in RF. If Hill can NOT hold onto CF, then Greene may take over as the starter there, and Grossman becomes a regular in RF.
At that point (if Hill is in rehab at AAA or something), then we're looking at giving another OF'er a chance, such as Cameron or Reyes.
Also, one other point: If Miggy is still on the team and playing 1B, any of the above bats except Hill can take over the DH spot for some PA's.
I'll let Hinch sort out all of the above... But on a guess, based on the above and between the 3 OF spots and some DH-duty: Baddoo ends up with 400 PA's, Grossman 550 PA's, Hill 350 PA's, and Greene 600 PA's...