My kids are going to a concert there in September. Is there room for me to park an RV there to stay while they are at the concert?

No...parking is tight and the surrounding neighborhood sketchy

You're asking to get stuck in the gravel lots with an RV, that is if they let you in. A better alternative would be to either go to the concert with them or park in one of the lots down the road and take an Uber/Lyft to the venue.

Not really. The venue is in an entertainment complex with just the most basic parking. An RV would not be easy to manuever in the area.