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At matchpoints, it seems bad to me to let the opponents play undoubled in their 5-2 spade fit when the odds are good that it is your hand
What about the auction makes you believe that the odds are good that it is your hand? One opponent opened, the other bid a free 1nt. That alone tends to account for a min of 19 hcp, it would be rare for your side to have balance of power. Furthermore, they don't have a true fit, which means you are unlikely to have a fit. If partner had any values & a suit fit he is supposed to act over 1nt.
I think it very unlikely that it is your hand, and exceedingly unlikely that you can make a 3 level contract. Partner would have bid over 1nt if that were the case. Beating 2S undoubled, if it's possible, will be good enough, there's no partial your way to protect.