Thanks you for sharing your experience
@LunaSilver. Wow! I agree with
@MaraudingMagpie that the end results looks really good! You can't tell there was a mark on the front and the back doesn't look bad if you didn't say what happened.
I recently bought the same Bridle Top Handle bag and it was in pretty good condition except for some indentation marks on the top left and back pocket that were likely from long term storage. I only did surface cleaning with a few drops of dawn and a little vinegar combined with water, then rainse off well with vinegar and water. I usually don't dunk bags that I'm uncertain if the material will do well. The indentation improved some after I went over the back multiple times with moist paper towel and hair dryer on low heat.
The first two pictures are before and then the after