There is an uncut version with more gore, but is yet to be released.
At the breakfast scene at the farm, Robert (Hugh Sheridan) says 'I've seen 'Charlie's Farm'.' Bernie (Nathan Jones) played Charlie in Charlie's Farm (2014). And the farm is the same location as Charlie's family's farm.
Unfortunately Nathan Jones had a falling out with director Chris Sun after the film's release, making any plans for Nathan Jones to appear in the proposed sequel for Boar and Charlie's Farm highly unlikely.
Cast member Steve Bisley and Roger Ward both co-starred in the original 'Mad Max (1979) movie whilst actor Nathan Jones worked on 'Mad Max: Fury Road' (2015) as did about half a dozen members of the 'Boar' (2017) crew.
One member of the cast and crew, actor Chris Haywood, worked on the earlier classic Australian wild boar thriller Razorback (1984).