Granted, my hearing is pretty lousy (sucks actually) but that sounds more like a knock more than a tap. Knocking is generally more serious than tapping as tapping often points to valve lifters and knocking more in the line of rod bearings or a faulty harmonic balancer.
How much do you trust your partner’s driving habits?
I assume the oil was changed at 150k so I might ask if you have raised the hood to check the oil level since that 150k service?
In that case, then–obviously–we can rule-out a tire defect.
If the engine is tapping/knocking at idle, that could be the result of a currently low oil level, or it could be an indication of engine damage from a consistently low oil level, ergo–lax maintenance in the long term.
None of those possibilities bode well, unfortunately.
I’m not buying that carbon canister theory. Even with my pathetically sorry auditory abilities it sounds more serious than that even after listening to it several more times. That comes across as a solid thump to me.
I might ask again. How many miles did your partner put on the car and how certain are you there was no automotive flogging going on?
I’m not trashing this person so please do not take it that way. The first few years my daughter was a driver she could not make a right turn without curbing the wheels. She would deny it but the skin marks on the right side wheels/tires said otherwise. Thankfully this habit died after a while and she became an excellent driver.