One thought that struck me that hasn't been commented on, is the whether MinAmb can, under it's legal charter actually rescind a previously issued permit without due cause.

The legal situation of an already issued permit as is the case with GRZ and Brisas is quite different to denial to issue new permit which is the problem the KRY is facing. Undoubtedly, MinAmb can refuse to issue a new permit on specific grounds or due to a recent change of policy, but does the law allow them to rescind an already issued permit when the only apparent grounds are "we changed our minds"?

In most countries, a permit can only be rescinded if the recipient of that permit fails to abide by the conditions of the permit. As GRZ was never allowed to start to build Brisas, because of the non-issue of the Initiation Act then they obviously cannot be guilty of any breaches of the terms of the permit.

I know that the rule of law in Venezuela is best described as capricious, but certainly random changes to the rules at the whim of any official and outside written law and fair business practice is going to be hard to support in any reasonable court of appeal anywhere.