Reverse sear steak disappointment

Hi all,

Loving my new blackstone so far but I went to reverse sear some steaks tonight and was a bit disappointed in the end result. Was hoping to see if I did something wrong.

I only turned on my center left burner on my 36”. I gave it 15 minutes to heat up on full heat with my propane fully opened. Once I got there I put vegetable oil on the griddle and put my steaks down for a minute each side. It barely seemed to cook the outsides. Please note I have the wind guards installed and my propane is over half full.

Feel free to let me know if I did anything wrong as I feel it should definitely get hotter than it did to get this result. Thanksn