Please let this notion go … Roon is not blocking anything, if the files are in a supported format (and with no special chars in the path) Roon will import. To aid trouble shooting it’s is worth a reading Roon Knowledge Base.
I’m curious as in this earlier post it seems you where able to import and play them (albeit with mixed results) … has anything changed at your end?
I’m assuming this is aimed at Roon so let’s tag @support for them to answer.