Is there any implementation of any PCP-verifier (for any NP problem) researchers can download and test? No matter if it is a github entry with actual downloadable code or just a (reasonably detailed) pseudocode description. That code can be extracted by a careful examination of the proof of the PCP theorem, but writing it fully from scratch seems like a cumbersome and redundant task for anyone interested in playing with it. We don't mind if it is the Hastad's 3-bit version or any other else.
In our case, we are interested in observing the (empirical) probability that PCP-verifiers give $yes$ answers when the word $x$ under consideration belongs to the target language $L$ but the certificate $\pi$ to be checked is not right. This probability is bounded by definition if $x\not\in L$ (e.g. $prob \leq \frac{1}{2}$) or if $\pi$ is a correct certificate to prove $x\in L$ ($prob = 1$), but it is not in that particular case. We wonder what the actual performance of PCP-verifiers is in that particular case.
Any paper reporting actual experiments running PCP-verifiers would also be a great lead.