There are a number of ways you could go about it. These would be procedural matters. The core procedure that needs to be in place is something to handle both, (a), when somebody doesn't have an opportunity to vote because of some kind of network issue, such as when the website goes down and you need to be able to recover from it; and (b), if it is detected that a member's vote was changed by accident, error, or otherwise. There needs to be a method to recover from both of those.
It certainly seems that you may want to have at least some kind of tiered or staged announcement of the vote outcome, a sort of preliminary and then final vote. You can be optimistic about it and announce a preliminary result, subject to the CSE or whatever. IT security might want to apply to it afterwards.