Okay so I added that and I found that those variables change when I walk around. I think the values it's reporting are the entity position relative to me. I also added a print statement in onCollideWithPlayer in my entity class.
Here's some results. Iv'e removed a bunch of lines with insignificant changes for legibility.
When I was moving around and towards it.
render at [x,y,z] = [-0.0688205783826561,-0.6200000047683716, 1.8603158817116423]
render at [x,y,z] = [-0.06856183817012607,-0.6200000047683716, 1.9326404313910075]
render at [x,y,z] = [-0.06830309795759604,-0.6200000047683716, 2.0049649810703727]
render at [x,y,z] = [-0.06556813480119672,-1.6200000047683716, 2.735793783717895]
//Big cut out
render at [x,y,z] = [0.14993124868499308,-1.6200000047683716, 2.6901420373826]
render at [x,y,z] = [0.1494137597773033,-1.6200000047683716, 2.616952694172994]
render at [x,y,z] = [0.14891149117158875,-1.6200000047683716, 2.5169638530804264]
render at [x,y,z] = [0.1484092225658742,-1.6200000047683716, 2.404049388770545]
render at [x,y,z] = [0.14789173365818442,-1.6200000047683716, 2.279212722030593]
render at [x,y,z] = [0.14737424479574202,-1.6200000047683716, 2.1454823556259157]
render at [x,y,z] = [0.1468719761446664,-1.6200000047683716, 2.0116582882938587]
COLLIDED WITH PLAYER
render at [x,y,z] = [0.14636970753895184,-1.6200000047683716, 1.875531413200008]
render at [x,y,z] = [0.14585221867662312,-1.6200000047683716, 1.7326454368743498]
render at [x,y,z] = [0.1468719761446664,-1.6200000047683716, 2.0116582882938587]
COLLIDED WITH PLAYER
render at [x,y,z] = [0.14636970753895184,-1.6200000047683716, 1.875531413200008]
render at [x,y,z] = [0.14585221867662312,-1.6200000047683716, 1.7326454368743498]
When I hit it with a snowball. I opened the main menu right as the glitch occurred.
render at [x,y,z] = [-1.0521818682104822,-1.6200000047683716, 3.2085209891840236]
[21:44:55] [server thread/INFO]: Saving and pausing game...
[21:44:55] [server thread/INFO]: Saving chunks for level 'New World'/Overworld
render at [x,y,z] = [-1.0521818682104822,-0.6200000047683716, 3.2085209891840236]
render at [x,y,z] = [-1.0521818682104822,-0.6200000047683716, 3.2085209891840236]