Part of the problem with this particular steak was the uneven thickness. Sounds like it was an end piece.
Next time you get an uneven piece like this, you might consider a reverse sear technique. Basically, you roast the steak in a LOW oven to an inner temp of about 100 for rare, slap it on a blistering hot pan for the sear on both sides. This is just for exterior sear, not really cooking, let it rest a bit, and then eat.
This will give you more info
Reverse Sear Ribeyes - Discuss Cooking Community