You forgot to include the Phillips refinery (and another that slips my mind currently) to your capacity numbers generated from OK...
Phillips is in Ponca City. You might look at a map for that. About 300 miles. It’s closer to Kansas City. Phillips does have a small pipeline from Ponca City to Oklahoma City, but it pales beside the northbound capacity of Explorer from the Gulf Coast to DFW and beyond. The Sweeney refinery is a little bigger than their Ponca City unit, but they are pretty close to the same size, so I won’t argue capacity on that.
As for other Oklahoma refineries, there’s Holly in Oklahoma City (about 150,000 bpd), and the small Wynnewood facility (70,000) No way they can step in to replace Exxon, Valero, and Shell.
Back to Phillips - there are only a handful of Phillips stations in DFW, although I realize the gasoline in the tanks is largely fungible and that additive packages are really all that is proprietary and that there are several ways to handle that, although only a Democrat tort lawyer would pay any attention to additives in the current situation.
I did hear last night from non-media sources that Texarkana was running out of gasoline, as well.