He had tried, unsuccessfully, to get into the stadium twice...but, but, he was no terrorist...we know that because his father, the FBI and the President of the college told us he wasn't.
actually what that told us (or confirmed for some) is that Fedgov will absolutely deny any actually attempted terrorist action unless it is so spectacularly successful that it simply cannot be explained away, e.g. 9/11/01 attacks.
They had his father out doing talkshow circuits within days of his death. that alone was a tell.
That guy was not Muslim. No evidence indicates he was a convert either or had any connection with terrorists. Rumour does not pass as evidence either.