Wait. Wait. Wait. I missed something the first time.
The TXG’s are different between the two ZFS members:
sdc2:
txg: 17236783
sdd2:
txg: 17236778
@HoneyBadger, is it safer and simpler to import the pool in a “degraded” state, using only sdc2. Then later determine whether to resilver or replace the other member of the mirror afterwards?