i might just be seeing things, but it looks in that last bright picture that your fish may be a fader. i am new to flowerhorns, but my bp started to look like that before she faded. like a said, i could be wrong and if i am, it isn't the first time.
i put a juvie fh in with my jack and he nearly killed her she was 3 inches and he was about 3.5. he bit all her fins down to nubs and she had a big wound between her tail and her anal fin. just keep an eye on your tank. they were fine for two days. then i went to work. when i got home she was floating on her side at the top of the tank. i put her in a hospital tank and she recovered in about six weeks. flowerhorns are the strongest fish that i have ever kept. i have seen other fish die from alot less.