Trigs 9-16 are nothing to do with plays free … nothing
Those play the machine at the current settings, they’ll do so even if the seq is off, it starts a machine, plays the sample (if assigned) at current settings
Plays free only applies to Trigs 1-8 and will only work if there are Trigs on those tracks and only if each track is set to plays free independently
Fn+Bank defaults to the global options, you then need to select each track manually and set it to plays free, but that track will need to have trigs on it … you are manually playing the sequencer, not the machine per se … so you need trigs
If the sequencer is playing and it’s set to a finite length, then the quantize will work fine, well at least it all works exactly as advertised here
EDIT: just saw this was resolved above !