Looks like the CRJ, is taxiing to the gate (immediate right turn), can't tell but it looks like that could be a wing walker on the left side of the picture. The MD-90's look like they are taxiing out for departure. ?????
I think the CRJ turned into the CRJ's left turn, as there are multiple regional jet aircraft parked in that vicinity at its side of Concourse C. The two FL 717's might have left from its portion of Concourse C.