I'd like to know about this as well, had pretty much the same scenario. They were fine before we went on vacation for a week and even though we had a neighbor watering who is very relaible, it was crazy hot during that time. When we arrived home I thought they just needed water, but they never did perk up even when I trimmed some of them back. They all resembled impatiens that had gotten zapped by a frost, all skinny legs and few blooms. Sadly, I pulled them out about a week before Garden A to Z reported on it, but I suspect we had the fungus too.