My wife and her Black co-worker .. I need your advice please !!

It’s kind of obvious. Duh.

The thing is you say you almost got divorced because she was cheating on you before so you stopped… you need to talk to her and set some ground rules if she is going to and you want her to fuck the guy. It sounds like what you want is for her to share with you when she gets fucked. the problem is that “cheating” may be part of the turn on for her. Maybe you can get her to tell you more this time around…. or maybe you can have her tell him he should tell you and have him send you pictures and video when he fucks her. But you and she need to talk a lot more and come up with rules.

this can be a risky area. if we had emotional feelings before that nearly had you parting ways..why would a new guy be any different?
if you are actually ok with a limited adult agreement eg occasional discreet fuckings .. or do we want more ? maybe wife found you too eager etc?
a proper adult honest open chat can set out parameters that have you both feeling relationship is being expanded and rewarding.. if she feels used? dirty etc then it will fail. if as you say she is now interested in him and dressing to please him.. then she ought to be honest if she wants to have a physical relationship with him. are you ok with discreet sex? do you want to have more interaction ? eg see? listen etc .
all aspects need to be talked over so we are both confident where rules are set and we both agree . if it works ..then its often really rewarding and addictive. if we find it raises issues ..we need to be able to agree how to resolve. good luck. maybe if it plans out well .this site can hear more about it all.

You need to just come out and tell her: Hell yes, dress very sexy for your black co-worker and fuck his brains out!

Just do it!

Gracie: Chick with a Dick