As you've probably noticed, I didn't use the LR API for checking ownership. Now, this might just be me, but I couldn't find a way to get the owner's address or any other way to verify ownership in the docs, so I connected to Moralis for that.
Futhermore, I couldn't fetch a list of collections or list the tokens within a collection. So I resorted to hardcoding some "known" collections and tokens within them.