Dumping?
First...great job maintaining your weight! What you experienced is not what I think of as dumping...that is when the sugars and fat**** your bloodstream fast and you get an unpleasant reaction from it. For me, it feels like what I've been hit by a truck. Terrible abdominal pain, my heart races, break out in a cold sweat, feel compelled to lie down and if I'm lucky fall asleep as the pain begins to subside. Then afterwards I have a bit of a after-dumping spaciness. Rarely there is diarrhea but I'd had my gallbladder out with my first wls in '99 so maybe that is why?
Check what type of oil was used to fry those chips as well as the expiry date on the package. Maybe your body just can't handle that style oil anymore or as you say maybe it's related to your gallbladder issues. Were you nauseated as well? When my mom would have a gallbladder attack she suffered 'at both ends' as she used to put it. If you still have a relationship with your wls, give his nurse a call and see if she/he thinks it warrants a visit to your pcm. Hoping this doesn't happen to you again, it must have been very unpleasant.
Hope the rest of your weekend goes well!

It happened while I was eating....which was odd. I had just bought the chips but will check. I can have a reaction to sugar, (I have reactive hypoglycemia) so I am really careful with sugar. But hadn't really noticed an issue with fats before, other than the gallbladder. Won't be trying it out again, and I just had my annual checkup....but maybe calling them would be an idea. Thanks.
This is worth checking in with a doctor. After 17 years there is a good chance you are developing gall bladder issues. The surgery to remove it is pretty easy. I am almost 18 years and had gall bladder surgery about five years ago. I pretty much avoid fats but can eat potato chips with no problems.

Real life begins where your comfort zone ends