Asymmetric revocable commitment's revocation key
The revocation key is actually a blinded key that is calculated from the two parties' revocation basepoints and generated per commitment keys.

So for A's revocation key for a commitment, the public key is calculated from B's revocation basepoint and A's per commitment basepoint. B does the same but with A's revocation basepoint and B's per commitment. This results in a revocation public key who's secret requires a component from each party so each party individually does not know the key.

When a commitment is revoked, the two parties will exchange the per commitment secrets so they will only be able to know their respective revocation keys. Since the revocation basepoint secrets are not shared, each node cannot know the other revocation key.

The full details of the key derivation algorithm can be found here.