I just learned something very unnerving. Called a Wendy’s restaurant and asked if they had seperate fryer for fries and all things breaded. They say “Yes”. I press the issue a little futher telling the manager my Gluten concerns to which he responds…Well we do mix all the oils together when we strain the food bits out then re-populate the separate fryer with the mixed oil.
Not an expert but this sounds like a real problem. Press the issue folks. Separate fryers are useless if they mix the oil together.