I think it can be solved with some math.
As I said in the first post, there will be two thresholds: one based on the number of votes and the other on the number of voters(addresses).
Even if an exchange/pool gathers a lot of votes and can influence part of the threshold, in order to influence the other part, they will need to create multiple nodes (with more than 30k Algo to keep the incentive) and then vote manually on the website for each node.
For example, if we say you need 50% of the vote available and 50% of voters to get your funding, it seems like a strong enough mechanism to prevent gaming the system.