I think this is an interesting thought, but why would it not have detected the other car as an obstacle regardless of where it was trying to park. Would be interesting to see the video of the left side.It occurs to me that you were parking on the right hand side of the road?
In the UK it's not unusual to park the "wrong" way, but in most countries it attracts penalties and almost never happens.
Perhaps the program thought you were looking at a space on the left hand side of the road and was starting a turn towards that, not the one you thought it was after? Being a US program I suspect it isn't set up for right hand of the road parking.