Isn't there still a movement afoot, longneck, which promotes the preparation of foods (including meats) at surprisingly low temperatures over longer periods of time instead of higher temperatures lickety-split? I think so. And I think it's got a pretty solid footing.
Room temperature seems to be the proverbial culprit, generally speaking. But the kind of circumstance you share is probably just fine. After all, beef is not uncommonly consumed rare. Pork and poultry are the ones we have to be so careful with, always cooking them all the way through.
Anyway, just for reference purposes, it doesn't sound like your stew ever made it back down to room temperature before your wife resuscitated the appliance. It's hard to be precise without knowing what the initial temperature was (the temperature the appliance was set for in the morning), but if in the past one and two-thirds hours the core has fallen to not below 155°F after only one hour's stewing, certainly after six hours' stewing a mere two hour lull couldn't be expected to yield results much different from the ones you were able to measure.
Gas rather than electric is normally the preferred mode for generating heat when it comes to preparing food. This is especially true on the stovetop where not only subtle but immediate (and visible) changes in temperature can be achieved. So too in the case of your crockpot I'd have to say that, yes, use of a gas appliance would have made it alternately possible for you to just yank that crock out of its base and shove it into the oven for the day. But I'm probably speaking out of line, as it's also preferable to have maid service and a hot towel with your shave.
I speak out of want more so than wont.