Google will never do anything that involves hiring O(N) employees to support N customers. They'll always outsource things like support, repairs, etc. so that someone else can handle scaling people, while they just go on scaling machines. Given that, the only real possibility is that "some random dude" is going to end up fixing your Pixel.

On the other hand, the "who's never seen the Pixel before" part? C'mon, the phone just came out—if an i-device breaks on the first day, you'd better believe that if you take it to an Apple Store someone's fixing it who has never seen that device before. That's the fundamental problem of new hardware designs (especially when coupled to bathtub curves); you can't blame Google for it. Give them a month and every repair shop around you will have fixed plenty of Pixels.