The ones that just appear as a generic Vote Failed message (except for 0) are probably used by the VoteFailed usermessage instead... the two usermessages share an enum.
3 is VOTE_FAILED_YES_MUST_EXCEED_NO (i.e. "Yes votes must outnumber No votes." in TF2)
4 is VOTE_FAILED_QUORUM_FAILURE (i.e. "Not enough votes" in TF2)
Be aware that the CS:GO team has renumbered some of these and may do so again in the future.
It used to be that numbers 0 through 15 matched up directly with the values TF2 used. As it is, 0 through 8 still match, but the values that used to be 9-13 are now 14-18.
Incidentally, the attached plugin can be used to test CallVoteFailed and VoteFailed numbers on both TF2 and CS:GO, provided Valve hasn't changed the usermessages.
Edit: The commands for the attached plugin are
callvotefail 1 0
votefail 1
where 1 is the number you're checking and 0 is the argument for types that take that (leaving this blank will use the value 0). Requires the generic admin permission ("b").
Edit 2: Plugin needs testing, as Valve may have changed the team number argument for votefail around... they did in TF2.
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Not currently working on SourceMod plugin development.