Doubtful. That'd require a custom bill mechanism, and Kraken noted that they're using a standard, off-the-shelf bill acceptor -- the same type you'd find in a vending machine.
That doesn't help too much does it? Since you aren't permanently losing the money using a few 10s of thousands in cash isn't such a big deal.
True, but at least you would need unique bills to run through, and law enforcement can then track those bills.
Law enforcement can laugh at you when asked to track those bills...
So you basically need access to a cash business for a supply of fresh bills. Also for how long do they keep the serial numbers? After a certain amount of time it is possible for the same bill to enter the machine legitimately.