Cody and Thermopolis WY RV Parks

Thank you all very much for your input. I've taken this same trip on a motorcycle, but never in an RV. So, I know the traveling will be different and slower. The purpose of the first part of our trip is to go to the Headwaters Country Music Fest in Cardwell MT. So, we are going to head from IL to Glacier, staying 4 nights at Whitefish/Kalispell KOA, then on to Cardwell Store and RV for 4 nights. After that, we want to see Yellowstone and Grand Teton, and are staying at Yellowstone Grizzly RV Park in West Yellow Stone for 7 nights. We are interested in full hook-ups and Fishing Bridge was full. We then travel to Teton RV in Victor ID for 4 nights and then Coulter Bay RV for 3 nights (all we could get, will keep trying for more). After that, we have 2 nights, 3 days to play with before we start back through Buffalo to the Black Hills (have reservations for 4 nights at Elkhorn Ridge RV Resort in Spearfish ND and then back to IL. This 2 night, 3 day period is where I'm stumped. It's not much time. I'm trying to see if we should stay in Cody and see the town or even take a day trip to the Beartooth Pass? Or, are the springs in Thermopiles better? Has anyone ever stayed at the Oasis Motel and RV Park in Meeteese, WY? Is it a good location? If any of you have any comments on the places we have reserved, pro and con, please let me know. If there is a better alternative, I'd appreciate that information as well. Thanks, you are all very generous with your information.