Since communication (disconnect) has now escalated further to being berated and setting demands on me when she and he are together...she has now involved MY partner.
What? Are you saying...
You decided to go parallel and no contact and she's still bugging you demanding things? What demands? Then she's involving your partner to help her bug you?
There is nothing wrong with a separate, parallel V. Block her number and all other contacts -- email, social media, etc. Inform the HINGE that he can deal with her and all the wacky. You aren't dating her. You didn't pick her out.
If the hinge doesn't get it together? Can't keep things separate and drama keeps leaking over on to you on this side of the V? You might have to drop the hinge then just to be rid of all this.