That's a shame. The Wendy's closest to me (which I had an issue with many years ago) treats me very nicely. Sometimes they're a bit slow with doing the orders (I've clocked over 10 minutes when it's just 2 people ahead of me), but it's not an issue when I know that they're going to treat me nicely despite how rushed and stressed they must feel. As for what happened, I'd type up a detailed report of everything that you remember happening, set it aside, then make a separate report of additional details that you remember over a two day period. After that, reread what you typed, make any corrections you need to and work in the new details. Try to make footnotes of phone numbers you called and such so that things can be verified. Then have someone else read over it (proof read for one) and then ask any questions they might have in case you forgot to include something. Then after all of that is done, send a copy of the BBB and to their local police department (for the PD version, include a letter from your doctor verifying that you are indeed allergic to mayo, along with consent for that information to be used). What they did was criminal, as it could have caused you to go to the hospital. Yeah let that manager claim that you didn't have an allergic reaction. But when the police come asking questions and telling how you have a medical history of being allergic to it, I'm sure that manager will feel like a dumbass. You might also contact Wendy's corporate offices and explain to them what you are doing, that you are going to let that police department handle the matter, as well as include a copy of the letter (the BBB copy) but also note that the police were sent a letter from your doctor confirming your allergy. Also include that if you do not get a response from them this time, you will forward the letter to the news media, as you are sure that they would eat it up that a fast food chain doesn't seem to care that one of their employees tried to kill you. Point of it all? Well for one, gratification. You'll know that something WILL be done to make it right. Heck, who knows, maybe they'll offer you "hush hush" money, in fear of a lawsuit. If they do, just make sure that there's no clause included where you're prohibited from talking about the matter (except maybe to the news media). That way you can discuss it here. But aside from that, someone else with allergies might go there and not be as fortunate as you, and I do mean that in the most depressing way. 1½ days isn't a long time.