I can imagine that the fibers of the towel are not reaching into the dips and rises of the vinyl. Do you have any microfiber towels laying around? Terry Cloths will do also, but those are rare, and may leave lint.
I would certainly give it another go with a ‘plusher’ medium, that has a bit of a ‘pile’ so that the fibers have a go deeper into the panel.
- Spray directly onto MF (Not soaking wet, but saturated with 303)
- Wipe onto panel, spread as evenly as you can
- Wait a minute or two, and come back with another towel to wipe up the excess.
>> Just a note. I’ve ran across some dashes that would just keep on soaking up the 303 due to years of neglect. Multiple applications may be required.
Hope this helps, and good luck!