You put Robert's name in parenthesis is that because you were not sure or because everyone knew him as RP? If you are not sure if the R stood for Robert, then I can tell you it did.
In 1930, in Lawton is the family of Robert and Lottie Adams. Their children are: Irene Beulah Buford Ralph Kenneth Pauline Mary
It says that Lottie was born in Arkansas abt. 1901 and that her father was born in Tennessee and her mother, Missouri. It also says she married at the ripe old age of 15. And since, at the age of 28, she already has 7 kids (and most likely one on the way) that 15 is not likely an error by the census taker.
Robert was 8 years her senior marrying at the age of 23. He is listed as being a Janitor but it looks like he has something to do with a "School of Agriculture". It's not very legible.
I'll keep digging and let you know if I find anything else.
Also, I noticed that you did not post this message in the "Fisk" forum. That would be a mistake, Fisk and Fiske are completely interchangeable. My mother's branch never dropped the "E" but there are dozens of records where they are only listed without the "E", even though they never spelled it without the final "E".