A person who is just starting out but is not yet frum, who heard from his non-frum father that he is a kohen (and of course as is common aside from the neemanus issue, there is also the rov that his mother is a zonah) comes on a trip to Israel and is being carted around on tours. One of the venues is Maaras Hamachpeilah. Should the yeshiva and the rabbinical group leaders start giving him all kinds of advice not to go to these places with the group.
In such a circumstance the staffers and group leaders should say nothing. If at a certain point the boy becomes committed and clearly wants to deal with his Kehunah then he should be taken through the whole process of establishing his status and if necessary be taught the appropriate laws and customs of Kehunah should they apply.