What’s funny is that Kylo said something to the effect of “No one has been able to get out of you…what you did with the map” which indicates that FO people interrogated him as well.
Those are the exact lines, so with the torture droid in mind, and Poe’s line “You might want to rethink your technique,” I think the implication is that he’s already been interrogated using the droid, and the scene is actually subtly showing Ren as bigger and badder than Vader in some respects (Vader just used the probe and failed, but when Ren uses the probe and fails, he moves on to something far worse and a lot more effective).