Actually, I recall reading some time ago that the relationship between Emanuel and the obama’s had gotten rather frosty. I think they wanted to the run the city behind the scenes and just assumed they would once their boy was in there, but he actually wanted to run it - for better or for worse - himself.
If Rahm DID have real anger the other day, he’s been warned off by Obama/Clinton/whoever, since then, and told to try to turn the whole thing back on Trump, or all people. It’s almost laughable.