I’d start with @DaveR’s suggestion. If that doesn’t work try moving any open ones around and/or closing them to see if the missing ones are hidden behind them. Unfortunately the info about panel positions and sizes is stored in either the .json preference files or the .plist file, and I don’t know a safe way to edit those without a risk of causing worse problems. Deleting those files should work, but that will also abandon all of your other settings, which is truly a last resort.
I ran into the same issue and resetting the workspace worked for me as well. As a long time user on a PC…switching to a Mac…this issue has been a plague. I have to rearrange my workspace each time I start SketchUp Pro 2022…window placements, toolbars, etc. It’s cumbersome…and frustrating. Any tips to keeping the workspace the same?
For #5 you can get there in less steps by right-clicking in an empty area of the disk image window, and choosing “Eject SketchUp 2022”. Saves having to find the disk image entry in other Finder windows.