Indeed it does matter, i changed the loadSimplePLY argument to fit the path of the files whenever i changed their location. However i only tried the path relative to the python file. But your tip of using the absolute path did work!
The code ended up like so :
pc = cv.ppf_match_3d.loadPLYSimple(r'C:\Users\Stormholt\Documents\GitHub\opencv_contrib\modules\surface_matching\samples\data\parasaurolophus_6700.ply', 1)
Thank you for your help!