People with a doctor degree go for a dime/dozen. You just need to pass some tests given to you by your future peers. The One that tests the future priests has never been, is not, and will never be anyone’s peer.
I recently met a seminarian from Korea (preparing to become a diocesan priest in Austin, TX), and he told me the following story that happened to him.
He spent some pastoral time in a Korean hospital as an intern chaplain. One day the head surgeon was doing is daily round with all the medical interns following him with the outmost respect (we are talking Korea here, not the USA). When the head surgeon walked by him, he stopped and with the outmost respect he saluted the young seminarian, briefly chatted with him and left. Later all the medical interns looked for the young seminarian and asked him who he was, because nobody knew of him and they thought that he must have been some important genius if the head surgeon treated him with such respect. He told them that he was just an intern chaplain, and the medical students were puzzled that such a big M.D. would treat him with respect. Later came out that the surgeon was Catholic and said that he only saves lives while the young man will save souls.
Just use Father and forget about the Dr.