i work for one of the top 5 banks in the US and work in fraud detection and prevention. MOs aren't high on our list for detection or prevention. i'm on the tech side and no system i know of deals specifically with MOs. MOs would come under deposit fraud and i've never heard anyone talk about MOs. i imagine because they put a hold on the funds until the bank has been paid unlike checks there are lots different scenarios.
it is a good idea to have a good relationship with people at the branch,, because money laundrying investigations can be started by the branch through the "know your customer" program/reg.
https://en.wikipedia.org/wiki/Know_your_customer
if the branch reports you, they can't/won't tell you (against policy). they just report to corporate and it then grows legs.