Having worked a sys tems department that had to do the daily, weekly, monthy 'backups' on servers, although not for EA/Maxis ;-) I'm sure that the industry norm is that all backups are kept for 6 years (at least that's the time in the UK, sommat to do with tax and audits)
So in theory ALL of TSO files are somewhere, even if they are in storage somewhere. It may be that they will pull all of the monthly backups and extract the account info for any that were 'deleted' in each particular month.
Sounds like an exciting job for someone
thats if it already hasn't been done.