Sucks to hear, man. I think we all have run into a bad build/ barrel at some point or if haven't yet, will at some point. Doesn't sound like the Smith is being evasive or shady. I often wonder about barrel manufacturers. I bet with all the barrels they pump out they get a lot of calls and to them at some point they feel like they can't bleed out new barrels. Its probably hard for them to know the legit problems from someone's bad handloads.
Looks like you're on the right track about not beating the dead horse/barrel and cutting your losses. I would be tempted to mail the barrel to Hawk Hill. Not to be a dick but they may actually check it out if put in their hands with no expectation of compensation. If they see a problem they just may do the right thing. HH has an excellent rep. If they switched steel distributors and this is a data point of feedback on that steel they will know it.
I am fortunate enough that my Smith is an excellent shooter and sees things from a shooters perspective. He has a good reputation of identifying bad barrels and working with the manufacturer to get a new barrel. If he saw those groups and velocities he would definitely to take action and own the problem until you were shooting at your expectations. I've used Smiths in the past that once the gun left their shop it was pretty much your problem. They wouldn't say that, they would answer your emails for a while but it was pretty much like HH's answer. They would give you an ambiguous, educational answer about all the possible reasons your barrel is shooting like that, but they weren't saying the magic words like Defiance did, "send the gun to me and I'll check it out".
If you're looking for a good Smith and are dealing with folks distant from your locality. I heartily recommend Harless Precision in Colorado.
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