Contrary to popular belief, the Mears American Heros car IS coming, just not yet. If you notice all the promotional material for the American Heros program, the #25 is not on there...the deal for that scheme happened a little bit later then all the rest and they did not have time to come up with the Diecast before the race, as they did with MOST of the others.
I can't recall for sure, but I'm pretty sure it's due in late August-early Septemeber.
Be patient, it'll be here.