General aviation pilot reported a near miss while on final approach to land at a non-towered airport in VMC conditions. The pilot did not have the conflicting traffic in sight during the approach and landing; but observed the other pilot perform a go around as the general aviation pilot was on their landing roll.

Narrative

I was arriving to MYL from the South; descending through about 9000 MSL; and had cancelled IFR with SLCC. They had pointed out traffic parallel to me and TCAS had shown it as well; well clear and off to my left. I was passing that traffic as I descended. Once on CTAF; XXX.X; I heard a call and transmitted my position about 20 miles to the South; inbound for Runway 34; full stop at MYL. The other aircraft; Aircraft Y; called inbound to MYL as well; but they were an Aircraft Y and I figured I was ahead of them and would remain so. At XA:26:04; according to ADS-B data; I was ahead of them slightly and 675 ft. lower at 8325 ft. I never saw them; but made several radio transmissions. One; in response to them calling out 12 miles South of MYL; I responded to directly with my mileage; 7.5 miles; from McCall. At XB:29 their ADS-B data showed their last position at .06 miles South of me (behind me) at 6900 ft. I was at 6125; 775 ft. below them. I had slowed to land and was doing 85-90 KIAS all the way to landing. The last report showed them still doing 160 kts. Nearing short final; Aircraft Y called that they were still 'no joy'. I replied that I was on short final; expecting that they were still miles behind me. I landed and was rolling out to taxiway A2 when I heard them call 'going around'. I looked to see them pass by me; midfield; at less than 100 ft. AGL and slightly offset to the left. I did not get any TCAS indications below 9000. There were no other aircraft on frequency at that time; although Aircraft Z; landed shortly thereafter. They never saw me either; got over the top of me; and didn't realize that they were overtaking me; and descending with me underneath them in their blind spot. At one point they called that they were number two for the runway; I believe; but can't recall for sure. They commented that I was going to slow (?) so they must have seen me at some point? But; why then the low pass instead of just taking spacing? Unless their aim point on the runway was halfway down and they remained too steep to find me until the very end? I believe their speed and descent profile were contributing factors; but what I can't understand is why my TCAS didn't go off! I am assuming that they didn't have ADS-B(In); or they would have been able to locate me.