April Fools'21: Trouble with g-2

On April 7, the g-2 experiment at Fermilab was supposed to reveal their new measurement of the magnetic moment of the muon.  *Was*, because the announcement may be delayed for the most bizarre reason. You may have heard that the data are blinded to avoid biasing the outcome. This is now standard practice, but the g-2 collaboration went further: they are unable to unblind the data by themselves, to make sure that there is no leaks or temptations. Instead, the unblinding procedure requires an input from an external person, who is one of the Fermilab theorists. How does this work? The experiment measures the frequency of precession of antimuons circulating in a ring. From that and the known magnetic field the sought fundamental quantity - the magnetic moment of the muon, or g-2 in short - can be read off.  However, the whole analysis chain is performed using a randomly chosen number instead of the true clock frequency. Only at the very end, once all statistical and systematic errors are determined,  the true frequency is inserted and the final result is uncovered. For that last step they need to type the secret code into this machine looking like something from a 60s movie: 

The code was picked by the Fermilab theorist, and he is the only person to know it.  There is the rub... this theorist now refuses to give away the code.  It is not clear why. One time he said he had forgotten the envelope with the code on a train, another time he said the dog had eaten it. For the last few days he has locked himself in his home and completely stopped taking any calls. 

The situation is critical. PhD students from the collaboration are working round the clock to crack the code. They are basically trying out all possible combinations, but the process is painstakingly slow and may take months, delaying the long-expected announcement.  The collaboration even got a permission from the Fermilab director to search the office of the said theorist.  But they only found this piece of paper behind the bookshelf: 

It may be that the paper holds a clue about the code. If you have any idea what the code may be please email fermilab@fnal.gov or just write it in the comments below. 

Update: a part of this post (but strangely enough not all) is an April Fools joke. The new g-2 results are going to be presented on April 7, 2021, as planned.  The code is OPE, which stands for "operator product expansion", which is an  important technique used in the theoretical calculation of hadronic corrections to muon g-2: