It seems to me when bats find a window shutter, plywood or other random spot it’s usually one or two bats and they seem “off” to me. I wonder if they have been kicked out of the main living quarters for some reason.

Let us know how it works.

They are very difficult to get bats to take up residency. Smearing bat guano on the inside of the bat house helps , but still difficult.
Bat Conservation International , one of the most knowledgeable authorities on bats once tested 20 bat houses in different locations with the up most care and science to get bats into the bat houses , I think they were successful on 3 out of 20.

Bats are very , very picky on where they want to live. Location , direction , temperature , sunlight/shade , food sources , wind and much more affect where they will live.

That said , hang some window shutters in the right place and bats will find it.

In summary , plan for failure with a bat house. If it works , you have unlocked the secret code that only bats know.