PSI stickers have become a bit of a problem even with precautions to keep them out of general circulation. The issue is not just a sticker getting on a tank that's not been properly inspected but rather the lack of association with a shop and their liability insurance on an individual's PSI sticker. If shop B fills a tank inspected in the last year by shop A and it explodes and damages shop B and/or injures or kills a shop B employee, there will be some shared liability for the accident. If the same tank had a PSI sticker on it, the individual is for all practical purposes much more judgment proof and shop B's insurance company is on the hook for the whole incident. That makes the shop's insurance company a lot less happy, and thus you have movement toward rejection of filling tanks with stickers other than the shop's own stickers.
In some areas, local shops will fill each other's tanks, but will not fill tanks with inspection stickers from other out of state shops, legitimate or not, as those shops have not agreed upon any common protocols.
At the other extreme, there are places that look for a current hydro test and don't bother with a VIP sticker at all. I see that mostly in cave country where there are a lot of traveling divers, and where there is some assumption that the individual at that level probably uses better than average diligence in tank fills and inspections given the demanding nature of the diving.
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I agree the compromise here should be along the lines of draining the tank and pulling the valve for a quick inspection to ensure it is clean, free of rust, pits, contaminants, etc and is odorless. Going into more detail on a tank with an existing current VIP from another shop probably is not necessary, and that minimal inspection only takes a couple minutes once the tank is drained, and charging a couple bucks for the cost of a new o-ring and some lube is reasonable.