More questions in NE, please help

CMG is not even in the US. They can not garnish.

I have not heard of PDM. Does that stand for something?

It sounds to me like they are trying to scare you by using some SS number babble.

There is also a Phoenix Debt Management that goes by PDM. There are a few threads here about them if you do a search above.

PDM deals entirely with pdl debt which are mostly illegal.
I have not dealt with them .
Wage assignments are voluntary and it can be revoked whenever you want.