Hi @AaronTank
I think you should be able to achieve that with two different folders.
With two folders, you could assign the same machine template to each of them, and then apply custom account-machine mappings to both folders.
This way you should be able to map a single, specific robot account to your machine in one folder, but multiple robot accounts to your machine in the second folder.
This would allow you to simply leave the execution target as Any User/Any machine, because the underlying folder setup will take care of the proper division of the workload between the available mappings.