How much of a coincidence it is that:
1. He decided to learn cat language
2. Teach the oher guy about it.
3. The other guy actually mastered and remembered it.
4. He became a cat (without having a reason to expect it as possibility), while keeping memories and conscience.
5. By chance he encountered the other guy so they can communicate using cat language.
Nah, she smiled when they were announced demoted so it's probably the opposite and she hated his guts.
He is the type of person to use little girl as a hostage after all.
So this Saruta seems like the same crazy guy that approached by UN based on what the cat saying.
But boy the part where Nekohira consciousnesses slowly fading just when he get the chance to die as human.... That's pretty dark...