I think it is way too early to call Lomong a medal contender, let alone a gold medal contender. Suppose that he didn't miscount laps and that Teg had led the penultimate lap in 60. Suppose further that even after that 60 Lomong still had a 54 in him to close. Instead of splitting 54,66 he would have split 60,54 and finished in 13:05. So to recap, Lomong's best case performance at Peyton is a 13:05 with a 1:54/:54 close. Keep in mind this was an evenly paced and rabbitted race with perfect weather conditions. This is good, but I wouldn't be surprised if everyone in the Olympic 5k final is capable of this. Certainly, every Kenyan and every Ethiopian will be (not to mention a bunch left off their teams). Then you have Lagat, Farah, and probably Rupp too at the very least. Perhaps other 1500m studs will step up to the 5k like in the past (El G, VN).
At this point, Lomong is still not a lock for the US team. I think Lagat is a lock, and Rupp is clearly the best of the rest (with Solinsky injured or whatever). With one spot left, I'm not prepared to say that Lomong will definitely get it over Teg, possibly Ritz, possibly Sol, possibly the rest of the field including other potential 1500m runners.
Don't forget that Lomong made the world indoor team in the 3k. While it is impossible to know where he is at in his training the fact is he has done some racing this year. Teg has not, so while Lomong beat him handily don't automatically assume he will continue to do so for this whole season.