I don't know if QUIESCE is a logged operation (looks like it is, based on your post)
Looks like the comm between the primary and standby is in place.
Then, why not do a normal TAKEOVER ?
If your client ip is removed, then you have no transactions in progress. Even if you do, they will just fail and not cause any data issue.
AFAIK, UNQUIESCE requires a db connection and not sure how you will do in this scenario.
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