Perform retries for getting source and target replication markers

1) In the Replicate method, there is no try-catch after 'while (replicationTargetMarker.TimeWindowNeedsReplication)'.
Are any exceptions in that fragment expected to be caught by the callees?
2) Also, wondering why there is not a single try-catch for Replicate method instead of multiple try-catch blocks? I see that you reset the counter 'failures' after every try-catch implying 10 retries for each step, but, perhaps, 10 retries for all the steps included is reasonable