I make known hybrids with some regularity and have good handle on how they vary. The same hybrids make good reference vouchers. That fish does not fit well with any hybrids I have made, which includes Redear x Bluegill. The fish being a creten does not help.
Look at those pelvic fins. They appear to be approaching jet black. Only two Lepomis I have worked with show that characteristic, Redear and Spotted (not Red Spotted) Sunfish. Spotted / Redspotted from the integration zone to show it but far removed from location of interest. The Redear hybrids I have made do not show the greenish cast.