I’d report them to the health department regardless if they were helpful or not.
There unwillingness to try and do the right thing as by refund or offer for trying other meals free, poor business skills.
As for the plastic ? They have probably tossed it out right away, it’s a “ he said she said “ situation now , sad. You no longer have any proof.
I’m glad you are trying a different meal service. Hopefully you find one with quality products and good service.