My thought … simply don’t bother with DNSSEC for that domain.
Why pray tell would you possibly want to do that? This seriously makes zero sense.
You do realize that MiaB does not use BIND as the authoritative name servers, correct? I told you in another response somewhere that you do not ever edit the zone files. This is in the same vein.
You really have not studied this project enough to understand how things work. I highly recommend that you read through the scripts and get some understanding, rather than just throwing things out there that you think might work to solve some non problem.