Exactly. The points can only be collected in the name of the traveller plus most programms only permit ONE individual membership.
I would advise them to enroll in a small business programm to profit from certain comissions the airlines provide like points, upgrades and even free tickets (LH Partner Plus Benefit, AA Business ExtrAA etc).
In the end say if they want to use the miles for corporate travel you agree but only if you upgrade your current tickets into the next higher COS when travelling for them.