This is something like official: Yemeni Troops, Backed by United Arab Emirates, Take City From Al Qaeda
..."Groups of Al Qaeda fighters fled the city in cars. I think they escaped towards mountains far from Al Mukalla after about 20 Aqap fighters were killed," Salem told The National.

Local tribes are believed to have convinced the militants to leave, he said.

“We entered the city centre and were met by no resistance from Al Qaeda militants who withdrew west" towards the vast desert in Hadramawt and Shabwa provinces, a military officer told Agence France-Presse.
...
Locals report the AQAP tried to give a fight, but then suffered heavy casualties to Emirati (probably Saudi too) fire-power, bow and fled the battlefield.

Bottom line: Mukhalla is now in Emirati and YNA's hands.