Certainly some jargon is typical in spoken environments but rarely necessary in written contexts, just as vice versa. Not that I have any specific proofs on the specific words in the survey, but given at least one example of curious slang ("fleek"), I wouldn't put it past Randall to attempt to find some.
Also, the fun thing about pronounceable neologisms is even if Randall made them up, there's a curious tendency in English at least to actually start using some of them.
