bug found in food. tried to inform restaurant and was rudely blown off. Posted on social media my finding. Restaurant saying i'm lying. what to do?

ordered a sandwich for take out from a local restaurant. upon eating it bugs were found. Kindly called the restaurant to let them know of the issue, ask for a manager and told them i was looking for nothing in return just wanted to inform them. Was rudely blown off. Posted a pic on social media of my findings. The post got shared over 1,000 times. The owner of the restaurant, staff, customers, and now local paper are saying it was all made up and a lie. What are my rights and options to get this resolved because it was made up. I was looking for nothing in return and now i am getting my name tainted.