When featureFlagReshardingVerification is enabled, on the coordinator, there is an additional step between engaging the critical section and waiting for strict consistency or critical section timeout, which is running the _shardsvrReshardingDonorFetchFinalCollectionStats command against all donors to get the delta in the number of documents since the cloneTimestamp. On each donor, this command blocks until the donor has written the "blocking-writes" oplog entry, which is after the critical section has been acquired.

In the case where the donor is blocked on acquiring the critical section (e.g. if there is an in-progress transaction), this command is expected to remain blocked. When the critical section times out, the _allRecipientsReportedStrictConsistencyTimestamp would get fulfilled by the ReshardingCoordinatorObserver with a ReshardingCriticalSectionTimeout error but the ReshardingCoordinatorService would still get stuck here since it doesn't also wait on that future. The fix would be to make `_fetchAndPersistNumDocumentsToCloneFromDonors` have a `whenAny` on both the awaitAllRecipientsInStrictConsistency() future and the getDocumentsDeltaFromDonors future, similar to this.