Not trying to point out the obvious but just in case....
If the plan had been a small plan in previous years don't forget the 80/120 rule. If they are right at 100 they might not still need an audit.
Edit:
I guess I didn't read the orginal question very well. He does say it has been a large plan for filing for years.
I would agree.
If something happens that subjects the participant to require a gateway (such as a 3% SH allocation, or a top heavy minimum allocation, or a forfeiture allocation), then the gateway minimum for this participant should not be offset by the cash balance accruals that are credited to the other NHCEs.