You cannot get factory paint coverage on repainted parts. If the place that sold you the truck actually did the paint work, shame on them for not wanting to warranty the work. I took one look at that from your blurry pics and could tell it was a repaint!
Got to be honest man. Not a big deal at all. I would just take it to a reputable place and they can paint the pillar and BLEND into the pillar down around the mirror area. You should not have to even go into the door at all. Any place that says they cannot is BS. That paint at the top of the pillar should run anywhere from $150-$275 depending where you take it to.(they still have to cover the whole truck in materials to paint just even one small area! Remember, they will bake your truck for an hour at really high temps. Now, your truck has already been baked. That means that your plastics like your mirrors and door handles are going to be dry looking and weathered. The sun does this to them but baking them after painting turns them old really fast. I opt not to bake my cars unless all of the moldings are off. Basically they will not warranty their work unless they bake. Most places are lifetime warranty not 1yr. No baking after paint = soft clear coat for 2-3days and no hard buffing for 30days.