Reinstate cleared AR paid transactions

I have a client who has lost a significant number of historical AR Fully paid transactions without explanation.  We suspect someone cleared history, but the client can't see how this was possible.

In any case, it would appear that only AR was affected and only paid AR transactions are missing from a specific date.

I'm wondering if anyone has reverse engineered the clear history for paid AR transactions?  We have a backup that can be used to reinstate the data, but obviously would rather not mess with live data and cause corruption.

The client is on Sage 300 ERP 2012 and MS-SQL 2012.

Any discussion on this subject is invited.   Thanks.