I had a similar stringing issue with PETG on my flsun Q5, where PLA was printing flawless without any strings whatsoever. Since your SR isn’t a bowden, that mostly rules out retraction distance IMO.

For me I narrowed it down to Z-hop: as the printer was lifting the nozzle slightly to move to another part of the print, molten filament oozed out - sticking to the print, and getting stringed across by the nozzle. I only noticed after recording the print (use at least 60fps to avoid the frame blurring you’ll get at 30> and watching what exactly was happening prior to the stringing. It took about 4 hours to get to that point 😭

If orcaslicer is based on Prusaslicer, wipe on retract with the initial distance set to 100% may not trigger a wipe. Try 70% or 80% instead. There’s another setting somewhere to force retraction when changing layers: enabling this will forcibly honor your wipe retraction preference when changing print layer.

I think you may still get stringing at the really spiky parts of the test print, given there’s no space for a wipe, and that volcano is going to hold way more molten filament than a V6 or similar

Hopefully someone with more experience can add their 2¢, it was pretty difficult to research info online when I had PETG stringing - everything just says “tune your retraction” 😤

Edit: I mixed up the SR with the v400! In that case, Another thing to check is your bowden tube pneumatic couplers - unload the filament and tug lightly on each to see if they’re fitting securely. If they’re loose, your extruder can end up moving the bowden tube itself back and forwards, which affects your retraction