I feel like Jacky's fav food would actually be Sandwiches because in the default Gem Grab environment, you can see Jacky's Drill on the side and beside it is a sandwich
According to Fan -Lore, R-T is probably Rik(The security Guard who wrote the journal thing during Starr Park CCTV) Who Fused with a TV in the security room , Thus R-T standing for Rik Televison, so R-t's food should be something something security guards like
As an R-T main and fangirl, I disapprove that theory. I personally think that when R-T was found, he was reprogrammed to take Rik's place. I think Rik ended up escaping as he said he would.