What you say may be true, but this backup you are talking about is not possible without a way to enforce it (i.e. make it actually work as a backup in case such a need should arise), so while trusting an entire overseas jurisdiction with your gold is definitely not the way to go, trusting a few people with your bitcoins doesn't really look like a much better alternative at all unless you can make these people return your bitcoins in some way. The latter basically means you will have some power in the future, but this may not be the case with Maduro in particular and dictators in general
What would you do? If you were running some sort of dictatorship, independent republic, or any other organization which tries to be as neutral as possible, but no matter how neutral you plan to be, there's always going to be allies and enemies due game theory
I'm not running a dictatorship, so I basically don't know
However, I wouldn't trust anyone in particular. In this way, if I wanted to remain in power (and have a working backup plan), I would definitely follow a policy known since ancient times as "divide and conquer" with the emphasis on the first part (i.e. the divide part). This element is about breaking up larger chunks of power into smaller pieces so that no one individually would have sufficient power or desire to question my rule (let alone actually trying to end it)
So if we consider financial aspect of my imaginary dictatorship (for that rainy day when it might come to an end), it still comes down to trusting no one specifically. And this leads us to the conclusion that we should built a distributed system of trust where failure (read, betrayal) of any particular element or part of it could not threaten the financial stability of the whole (read, my financial well-being no matter what the circumstances might be). Do I count as a good dictator?