The best thing to do would be to use the Merge Person page (http://www.wikitree.com/wiki/Special:MergePerson) to manually reject merges between the profiles. That way when someone else runs a search for matches, the profiles show up as rejected, and if they try to merge them together anyway, a warning pops up that the two have already been rejected as matches.
As added protection, you could do as other wikis do, and put a disambiguation notice at the top of the bio to distinguish between two very similar profiles, like cousins with the same name born in the same town or time period.
This is the profile for Jan Orescu, son of Piotr Orescu and Elisabeth Unknown. For Jan Orescu, son of Ivan Orescu and Maria Dvorak and immigrant to Wisconsin, see profile Orescu-###.