Responsa sur Shabbat 19:7

However, who could tell us that [this youth] definitely knew he wasn't circumcised? Does every ‎sixteen-year-old child know the nature of circumcision and the visual difference? Perhaps he was ‎modest and never looked at it his entire life. Think about it [further], due to our many sins there ‎are areas in Germany where the mohelim are severe sinners and do not perform priah [lit. ‎revealing; peeling off thee pithelium]! Many children are therefore as though they were not ‎circumcised [at all], for we learn, "One who circumcised without priah is as if he had not ‎circumcised." (Mishnah Shabbat 19:6)However, none of them know that they are not circumcised; ‎certainly, they are like" children held captive among non-Jews". Further, even if they were to learn ‎afterward that priah is necessary, they wouldn't know that priah had not been performed on ‎them. Moreover: Even if you would say that he knew that he wasn't circumcised and despite that ‎he didn't circumcise himself, one could argue that he did so because he didn't want to pain himself, ‎and not because he kicked[i.e. rejected] the commandment of circumcision. If so, all would agree ‎that he was only a rebel concerning one matter, due to his desires. It seems to me that even in ‎Hungary the custom is not to distance the grave of such a rebel from other graves - in Germany, ‎the custom is certainly not so - and so there is no legal reason to change the youth's burial from the ‎burial of other Jewish sinners. ‎