Mirror-image life obviously depends on chirality. But chirality is very relevant without it. It is a fundamental aspect of chemistry (and biology).

Yes, this sounds like a situation where progress in that field may have led them to go back and give more credit to the original experiments going in that direction

Yes.

The mirror-image life problem is just one (of many) issues directly impacted or resolved by this finding.

Yes, that should be evident from the first paragraph of each article.