Take as many photos as you can of each of the components,from as many angles as you can,paying particular attention to the barrel/upper receiver mating areas,before sending anything to any one.This coupled with what has already been posted here will ensure that you have recorded the matter as thoroughly as possible, so that you will be treated correctly on reappraisal by RRA.
RRA are a very reputable firm and will deal with you fairly and honestly.
K is correct when he states that the gas port in the gas block is oversized to accommodate some misalignment.The gas block/front sight post port is normally around 0.125"-0.158" as opposed to the barrel ports 0.070"-0.095",(depending on type),but you said you "thought the barrel turned in the vise" and "then noticed the gas port was out of line somewhat".
It was this description and the fact that the misalignment was that noticeable by eye that drew me to those conclusions.
As the gas port is drilled,(or EDM'd- some use this technique to dispense with the bore lapping to remove possible burrs), AFTER the index pin is installed ,(hence the reason for the number of barrels for sale profiled, B.E.'d and headspaced but WITHOUT gas ports drilled, available in the AR15 Parts section of this hallowed Site),then there is no real reason to have the port out of line any more than a couple of thou as the milling head should be indexed off the barrel extension pin centre before drilling the gas port.The mill table is just then traversed the corect distance to suit the application(whether CAR,Midlength of Rifle) and the port centre marked and then drilled.
This process can be done accurately with a standard drill press and using a jig and v-blocks, as I have described in another thread.
It would be extremely difficult to detect BY EYE, a gas port that has been formed a couple of thou off the barrel centreline.
It is true that "out of line" witness marks are left by front sight posts and gas blocks,but this is should be due to the fact that the front sight posts are aligned with the rear sight aperture at its theoretical (assumed) centre, and the gas block(without a sighting device)and tube is arranged with the carrier key bore and hole in the upper receiver,with all the accummulative errors these methods of installation can produce,and not because the gas port is out of line with the index pin.