I think part of why Vox hates Angel so much is becuse he undermines his authority at every trun. We even see think with him spitting in Vox's face. I don't think this is the first time he's snaped back at Vox. I can fully see him being rude as all hell to Vox only to in a ironic twist hide behind Val because Vox isn't aloud to hurt Val's toys.
We get explicity that Vox has been waiting to back hand slap Angel himself meaning that Val must have explicity been stopping him. Of corse not out of possession not protection.
Still the effect to Vox is the same. Angel makes it look like he has less than 100% authority because he does.
Vox also just can't stand known Angel doesn't like or repect him. If Angel at least repected him he could tolerate that.
Some times Angel is obviously asked to act like he gets along with Vox and Vox hates that more. He feels Angel is trying to lie to him even though Angel has littelry no say in the matter.

















