I sense you would be able to make 200m quicker with a few resource gathering bots instead of trying to get it with squeal (called 'Treasure Hunter' now)
Let's say you have 10 bots running everyday, collecting at least 1m a day each. That's 200m in 20 days.
With 'Treasure Hunter' you get 1 'key' a day. From what I could find in a very quick search is the *Very Rare* category has a roughly 0.1% rate of being picked. Keeping in mind the 200m doesn't always appear, we'll decrease it to 0.05% (being liberal with that). That's a 1:2,000 chance of getting the 200m. With the 10 accounts, it would take you 200 days to open chests that many times. Assuming, since you won't need all the accounts open at once, you'll have many more accounts though. So, in order to roughly get the same rates as traditional bots, you would need 100 accounts.
100 accounts, using a relatively obscure bot (more so now with 'Treasure Hunter' instead of SoF) is, in my opinion, a lot more labor intensive than merely 10 accounts running traditional bots. Even if you did manage to get a bot that auto logs into every single account, everyday, plays the game, checks for the 200m, logs out and repeats, there's still no guarantee you'd get the 200m. Also, in the same time period of 20 days, using 'TH' bots, you will always have only a 0.05% chance of the cash. Whereas with gathering bots, the percentages are probably in the 70's or higher.
So, all told, if you're considering botting, you're probably better off going with a method that's proven to be effective.