Am I out of line here?

[Bobbo539]

I play at Hollywood Park Casino In LA at the NL100 a descent amount. One thing I pride myself on is always being mild mannered and not whining or anything like that, and I always tip the dealers well.
Tonight I was observing a hand between the guy to my left who I was chatting with occasionally all night and another youngish guy accross the table with sunglasses who seemed to think he was the best player in LA. Anyways, on the river the guy to my left check called a 50$ bet (for a pot of about 200$) on a board on 9 7 6 2 2. The other player tabled 9 7 for top 2, and the player to my left showed me 10 10 shaking his head and was in the process of mucking when I held my hand out and told him he had the best hand, which was clearly audible from accross the table. The player to my left looked at the board again and said something about how he didn't see the board pairing, and tabled and won the pot. The other guy, ovbiously, was heated, and started telling me off, and then made the dealer to call the floor because he thought the pot should be his. The floor and dealer both told me I shouldn't have gotton involved, but say that since the player to my left never mucked and showed he deserved the pot. For the next two hours the other youngish guy reminded me of that hand and told me off about 50 times, including telling me that he would "f***ing kick my a** outside", until I finally left for the night.

I think I did the wrong thing, but I acted in the spur of the moment without getting a chance to think it over.

What should the correct ruling have been and was I wrong here?