I have searched quite a few sources but could not find a single clear example of zero complementizer (Value 4) with sabi 'know'. We found, however, an example of zero complementizer with bribi 'believe'.
Mi bribi a man gwe na Holland volgens mi, yere.
[1SG believe the.SG man go.away LOC Holland according.to me okay]
'I believe he’s gone to Holland.'
Source: Plag 1993: 47
Source: Wilner 2007: 73