These guys are humans just like you and me. Theres no point hanging on shit they say in interviews because we have no idea of context. For all we know, Frank had the bestest blowjob ever the morning of this interview. Or had a huge row with his missus the day he made the "I want to kill Brock" comments.
There is no real truth can be gathered from watching little edited snippets of fighters making comments. You can speculate wildly, which is fun in itself, but come to conclusions? No way.
In this interview, Frank simply looks in a really good mood. Thats it.