Yup!
There are a couple of things. A tight sports bra (with front or back fasteners) can be a good idea, particularly if it has a smaller cup size.
Alternatively, after top surgery many surgeons recommend using back supports as a chest compression device; you can get them at sporting goods retailers. I see from your message thread that you're in Alaska; I'm in the UK so have no knowledge of your retailers, but
here's one I googled which will show you what sort of thing I'm talking about.
You just wrap that around the chest, fastening the velcro at the front in the middle of the chest (or under an arm, if that's more suitable) . It squishes the offending parts & isn't visible under most button-up shirts. But be careful to ensure it doesn't affect his breathing.