If this is proven to be manipulation by the manager, it is possible that the manager included several alt accounts in his own campaign.
Does it mean that managers who are known to be trusted people can manipulate spreadsheets as well? I don't still have this idea as I think that those who are called managers are reputable and trustworthy people that can as well punished their applicants who are found cheating or violating their campaign rules and regulations. If a campaign manager does this then I can assumed most of the managers as well can compromise.
I know the creator of the spreadsheet can see all the edits, unsure if just anyone can see them. Most of the managers aren't going to manipulate the spreadsheet regardless as there are always eyes watching and why risk it?