Fill it out that you got a Pfizer placebo, but put that into doctor's handwriting. Malicious intent is (mens rea) gone, and when criminal intent can't be proved, there is no crime. Then again, check with a lawyer because I'm just a guy that hangs out here :)

In the UK, it is their policy that law that anyone who received a placebo is to be afforded all the rights and privileges of the fully vaccinated, particularly because they didn't know they got the placebo!