Indeed that would be crap. I think it would be pretty daft if he blew up as they're through on goal. It's a work in progress, they should be able to come up with a solution.Problem being, what if the ref decides, after reviewing, that there is no penalty, the defending team could have been in on goal with just the keeper to beat when the whistle goes to review the decision.
If the break is really quick, before time for a VAR review, I'd rather let it play out and if the breaking team score the ref immediately makes it clear that it's subject to review. It's either a goal for one side, or a penalty to the other. A massive decision obviously, but that can't be avoided.