Good God, I swear some people actively look for the worst in people, and to be offended. I think there's a very good chance that the Munich references were missed by the person in charge of the account. I certainly wouldn't have immediately picked up on them except for this thread expicitly pointing them out. Bear in mnd the person running that account is probably dealing with hundreds of tweets coming in - they probably just took it at face value.
As for the "dressing room" comment, he's likely just making a crack about the rather odd mix of genres. I find it unlikely that the players listen to much Frank Sinatra, so I suspect he's being a bit silly and making a joke. That's eminantly more possible than him making a Munich joke and thinking he'll get away with it.
There's no doubt that the original reply is a Munich reference now that I've looked at it properly, but I don't think the guy running the official LFC account picked up on that. It's a naive mistake, but an easy enough one to make - to assume the answers are in the same spirit as the question.
It's kind of sad how a bunch of you instantly assume the very worst, just to reinforce your gloomy worldview and, what, use it as another stick to beat Liverpool FC with?