Since there are no 1952 rpm's or omm's known what you're seeing is a die chip. These can be very tricky as you sometimes see what you want to see. Go to varietyvista.com and do a search of mom's and mint mark styles . Compare your coins mm to the style used in 1952 using the chart. You'll see what I'm talking about.
Also, here : https://www.ngccoin.com/coin-explorer/jefferson-five-cents-pscid-25/1952-s-5c-ms-coinid-14048 they seem to think some exist.
To be honest I've been collecting nickels since a kid, I have so many varieties in my collection , but never heard of a 52 S/S . Now you can ask Alan at coinzip.com about a roll of unc. 53 D's I have. We both thought they were D/D's and D/S coins. We picked out the best we could find and I sent them in all came back as die chips. I never like to say never after 97 years later a 1919 dime came back as an ddo worth 9+K.
