To recover the reconciliation reports, you might unzip backups of BR (or the BR data from larger backups) to folders marked with their respective dates.

When you open this data in BR it will turn off the interfaces to Ledger, Payables, and REceivables, which is fine.

Assuming you have regular backups, you can do find one to get a balance for each reconciled date. If you use backups made just before each clearing to history was done, you may find the error readily.