William-
Yes, you're correct on that point.
Fundamentally though, if an RIR actually did that, it's effectively the end of RPKI, and seismic damage to the internet at large. The entire foundation of this system is that everything must trust that the RIRs are the source of truth over what IPs are allocated and to whom. RPKI just provides a way to cryptographically verify it. If an RIR was forced to pull an allocation by an external party for "non-normal" reasons, then trust in that RIR is irrevocably broken, and we have much larger issues to deal with.