The friend has been identified as Corey Kimball. The press statement said Kimball reported Zippro missing around 4 p.m. Sunday, June 17.
"[Kimball] told authorities the two had an argument, so the friend left to go on a hike alone. When he returned, Zippro’s tent and backpack were still at the campsite, but there was no sign of him," the press release said.
National Park Service rangers and the Whatcom County Sheriff’s Office have been searching for Zippro, using ground crews and a helicopter, according to a report in The Bellingham Herald.
Zippro, a graduate of Johnson High School in Hall County, is described as approximately 5’11, 190 lbs. with light brown/dark blonde hair, and hazel/ blue-green eyes.
The missing man's mother, step-father and sisters live in Gainesville.
A Facebook page called Bring Casey Zippro Home!! has been set up to help gather information as the search for Zippro continues.

http://accesswdun.com/article/2018/6/686063/family-asks-for-help-in-search-for-gainesville-man-missing-from-national-park