No the burden is not on the one opposing the plan. You don’t spend millions of dollars on a plan that may possibly work if only you win a royal flush 3 times in a row in your poker game tomorrow even if it is theoretically possible.
If some kid goes to a bank “Hey I have a great plan to take over microsoft, lend me a million dollars!” Should we be surprised if the bank says no without giving a reason? First, prove you have what it takes instead of coming out of nowhere with all kinds of untested ideas.