Joe Ga neither returned to Mosul nor went to Baghdad...
Baghdad must have been in total chaos at the time, with that guy Steven constantly leaking to the media. The verbal battles must have been a mess, and Joe Ga didn't want to confront such a situation directly.
The information Aaron provided him was very timely, and Joe Ga decided to wait until ISIS's retaliation began and the situation became clear before going back.
Only then could everyone really sit down for a serious talk...
After all, everyone was still allies; this was just a mess created by some politicians for their own interests, with Turkey being the scapegoat pushed forward to take the blame.
Originally, that old lady Rashiri must have had a way to make Turkey comply, such as proclaiming in front of the media that it was a bombing error, which would be an indirect apology to ISIS.