While I understand where you’re coming from, in terms of the current legal situation, you are liable for mistakenly believing some license information when that turns out to be wrong.

The way that publishers, for example, avoid such pitfalls is by exclusively working with professional agencies that control the provenance of the work they license.

Watching anything isn’t copying nor showing and therefore safe. Practically, if you want to use any CC-licensed photos, I would advise at least a reverse image search.