I don’t want to nitpick here, but your prints look show some signs of underextrusion. Is this an older spool that has been sucking in moisture? Don’t think that explains the warping though, an enclosure (if you don’t have that already) could help a little with that. Cutting the sprockets out of sheet metal and mounting them on the print, is probably best.
Yeah your right-I’m not a printing guru -this is an aldi printer with old filament -this is quite big to probably 200mm round so I’m not surprised it’s warped - only has to be 1mm off and film sprocket won’t stay in -good for prototyping