So will Lomachenko’s Dad be in Usyk’s Corner?

Yes, it was Tkachenko (here's an old photo of him and Lomachenkos: https://image.ibb.co/caw0JV/Usyk-2.jpg). He's an experienced amateur boxing trainer, but I doubt he has any pro boxing experience at all (definitely none at the top level).
At this point if anyone really thinks that Russ Anber is Usyk's trainer... Well, just forget it, it's a joke.

But for Usyk to switch trainers like that is a recipe for disaster. He should select someone and stick with him. Even if it's Tkachenko — just keep him and work together. I would prefer James Ali Bashir back, frankly speaking...

 

Based on what I managed to hear, his comments in the corner weren't nice at all. After the second and third round he was saying something like "You're doing everything correctly and it's going nice for you". Trainers like that may instill a sense that the fighter is doing good, despite that he isn't doing enough (e.g. Algieri corner against Pacquiao).

I believe Usyk had just enough ring intelligence to adjust on his own.