Light aircraft instructor pilot reported that on the landing roll he observed another light aircraft overfly his aircraft with 50-100 feet vertical separation.

Narrative

I was flying Aircraft X on return from a training flight to PSP. We crossed TRM overhead at 1.400ft and entered a 45 degree entry to left downwind 17 at pattern altitude 900ft following another Aircraft Z. Aircraft Y entered left downwind 17 behind me. After the preceding Aircraft Z landed a Aircraft A departed runway 17. At this time I turned an estimated 1.2NM left base to 17. Aircraft Y turned left base behind me providing an estimated 0.7NM separation. Once Established on final I was flying a final approach speed of 65KIAS. Referring to ADSB; separation maintained by Aircraft Y continued to decrease. After touchdown of Aircraft Z I looked through the rear window to visually assess the separation maintained by Aircraft Y and observed the airplane was overflying the runway at low level; estimated 50-100ft. ADS-B altitude of Aircraft Y indicated a 100 feet height. I was in the assumption a go-around by Aircraft Y was executed; however no noticeable climb was present. I exited the runway at the next available runway exit F1. By the time I was initiating the turn to exit the runway; Aircraft Y overflew with a low clearance and continued settling for landing on the runway remaining beyond Aircraft Z.After clearing the runway I made a radio call and questioned Aircraft Y to briefly meet after shutdown. No response was received and I taxied in behind Aircraft Y. After shutdown I approached the pilot to discuss the safety issue that arose. He blamed me for 'using more runway than necessary which would force him to go around.' He referred to his passenger as being a CFII. Upon introducing myself to the person he turned out to be a passenger without any flying experience. My subsequent request to exchange pilot information was denied.