They'll have been over his accounts in detail, any other lump sum deposits from U. DAVILA should be pretty easy to spot - if you assume he did it more than once then you have to also assume the investigation to be completely incompetent.
So lets see if i have this right im a gambling addict chasing some extra cash and i only did this once.
Sorry as someone who as admitted to having been down this hole admittedly no where near his profile i just dont accept his excuses then saying it was only the once. I also said i only did it once its what you do when caught.