If you Auto Assign Owners for assets it will assign owners based on the last logged in user for that Asset.
The Suggested owner will be listed only if the below conditions are met,
1. Windows machines should have been scanned successfully.
2. The scanned machine should contain any Last Logged in User. Ex: Jeri.
3. The same user(Requester)'s login name should be inside the MSP application .i.e., If a machine is scanned which is having last logged user as Jericho, then in MSP under Requesters, a user named Jericho should be present with the Login name as Jeri.
4. The scanned asset's Account and Requester's account should be the same.