Kurzgesagt has a nice video on vacuum decay for anyone interested
I'm a bit curious as to what time span exactly they're measuring here? Because it's not like the whole universe would die all at once. Heck, vacuum decay could have already begun somewhere. If so, it would propagate outward at the speed of light, which is quite slow compared to the size of the universe. If it's far enough away, it may never reach us at all due to the space between expanding.
In any case, this is all theoretical and may not be an actual thing that could happen at all.
bold of you to assume they don't have even more struggles than what they listed off there