edit: I've only touched the root and it seems to be already a bit rotten, so I just pulled it out, hope for good!
So I have this Monstera plant that after some time of not growing I took out of it's pot to discover root rot, removed all the rotten roots and managed to get some healthy in a new pot and soil and it did managed to grow a new leaf and recover! Amazing recovery but now I have this ceramic pot with one hole at the bottom which drain pretty well but there's one root that comes out of it which I don't really know what to do about, what do you think? Pictures added.