Mkhatshwa, who left Siyavutha under a cloud last term, was recently fired by NFD rivals TS Galaxy only three games into the season.
Spurs CEO Freddy Mapulane broke the news to KickOff.com and confirmed Gumbo has also finally received his work permit.
"By the way Vusi Mkhatshwa is back with us, " Mapulane says.
"We finalised it yesterday, he is back as a second assistant."
Mapulane says the two parties have moved on after Mkhatshwa previously accused the club of owing him money.
"It is something that we didn't take personally. We are both gentlemen and ifit comes to work we should be professional about it. So it's something that is water under the bridge.
"Actually we learned from Highlands Park last season, remember that they brought in someone like Allen Freese and we were all shocked saying what are they doing? But now we see that in the NFD to have a good strong technical team it helps considering that our coach is coming from outside.
"Vusi has been in this league for quite some time. He knows the players, he knows the league, so we thought he might advise him better. I think that's a wise decision we took. He has signed for two years."
The Mpumalanga-based side will host University of Pretoria at Puma Stadium at 15h00 on Sunday.