The devils advocate in Catholicism is something very specific and not at all that. In order for someone to be determined a Saint there’s more or less a trial. One side presents arguments that say the individual has met the criteria by which one can be determined a Saint. The other side, which is called the devils advocate, attempts to poke holes in it and presents arguments by which the individual hasn’t met those conditions. They’ll do things like bring up sins and character flaws that persisted into the individual’s saintly period, as well as attempt to disprove any miracles the individual is said to have committed.