My Ender 3S1 has been doing that weird line on that specific print since I got it! My retraction settings are tuned in, and I'm using Gyroid infill with 30% infill. I attached pictures for another recent print I have done with the same problem! The picture shows the two opposite sides, and the line seems to go out of the print on one side and back into the print on the other. I cleaned what you suggested, and it slightly got better but the problem still persists. I also attached the GCODE, slicing it on Cura it also shows a straight line not the weird squiggle that shows in the final print.
CE3S1_Letter Stand Actual Final.gcode