tgifridays.co.uk é seguro?

I've been to TGI's on multiple occasions; normally finding the value and food quite alright. However, I don't go here anymore due to a bad customer experience. My husband tried their burger and became ill later that evening. Now, my husband doesn't drink alcohol and he does not get ill... like, ever (weird I know because I do all the time). Upon contacting customer services they stated that 'they had no further complaints that evening'; pretty much telling me I lied. So purely out of principle, I have never returned here and have told all my friends about this experience. The burger was bad, the customer service was worse.