Welcome to the iNat forum!
I think that there’s an existing feature request that addresses your question here:
https://forum.inaturalist.org/t/allow-gbif-and-bold-photos-to-be-used-for-species-pages-lacking-photos/30348
You could vote and contribute thoughts there.
There’s also a recent discussion on DNA sequence data here: https://forum.inaturalist.org/t/integration-of-dna-sequence-data/37814
that may be applicable.
In general, duplicating records from other databases on iNat wouldn’t be good practice, but (personal opinion) it seems like allowing images from BOLD in the same way as for other sources as outlined in the feature request above would be a useful feature.