Source: https://youtube.com/clip/UgkxvPUaAgZCQO5CtQX1xZcAUd1CVcbt_dPJ
From HBomberGuy’s video on Tommy Tallarico.
Thing is, you don’t actually need an adjudicator on-site to get a record. I don’t know the details, but I assume sufficient documentation is all it actually takes. To be fair, I don’t know for sure that this guy (consoles, not drums) brought in an adjudicator, just assuming he did considering the video is on the GWR official channel.
Also, considering GWR is just a publicity stunt, they have an editorial team picking out records they find interesting to put in their books, not just taking whatever is submitted that year as impartial observers.