Nice job an both steaks!
Kosmo’s videos are great! Malcom Reed also has one on cooking a steak for an SCA cook off that is very good.
Be careful with the rail temp on the grill grates. I shoot for 625-650 for my timing and rub combo. If the rails get to hot the grill marks can get bitter depending on your rubs. If I remember correctly Kosmo shoots for about 600 degrees rail temp with his rubs and timing.
BTW, the same method works great on pork chops, lamb chops, burgers, etc.. here are a couple of pork chops that I did in my PK360 using grill grates.