It would be unusual to get a non union with this fracture
pattern. The commonest type of 5th metatarsal fractures
to go onto non union are transverse fractures at the base of the bone. Yes light weight bearing often helps stimulate bone healing
. If the bone does fail to unite - i.e after 12-16 - weeks of treatment then operative fixation is indicated, if it remains symptomatic, with or without bone grafting
. I suspect you won't have any issues.