I agree with cooking hotter until they pass the bend test. But I am venturing a guess that your grate temperature was not an accurate 225 degrees from the looks of things. 3/2/1 at 225 deg grate temp will get ribs way more done looking than that.
Have you calibrated your therm? Did you take temp at grill level? Did you open the cooker a lot to peek or baste?
Jim - Another transplanted Texan
Former KCBS CBJ
Large and Medium Big Green Eggs , Black 18.5" WSM, Blue Weber Performer - Stainless, Green Weber OTG Kettle , Brinkmann SnP Pro, and a Stainless UDS. One retired Portable Kitchen grill.
Red Thermapen, Maverick ET-732, EdgePro Apex Sharpener.
Avatar is the original 1951 Weber Kettle