Paradoxically, Hoaki's broadcast was a big lie by omission. He didn't mention at all that humanity was beaten to submission already (wait no, I think it's more accurate to say that they were manipulated to accept their fate as inferior species rather than through dominion like in the first invasion). They're superior to humans in every way so I don't see this going well.
They overextended their hand and should have already been content to have gotten rid of the government leading them to the slaugther with a smile.
Though I'll admit it's possible the aliens would have done something about it learning that their pets had rebelled anyway. I think their only hope is if the aliens are so advanced and their society so utopic that it became ill-fitted to suffer an invasion and revolt. If they have no army since war and infighting became foreign concepts to those uber-civilized beings.
It might be likely. Most humans would freak out seeing a bipedal alien show up in their city, but they were completely chill with Sakaki showing up, whether the average citizen there even knew or cared about humans.