Maybe I'm naive, but we used to keep dyed hardboiled Easter eggs out on the counter for an entire
week. Not even refrigerated...and they were always fine.
And in England, eggs are displayed and sold from the regular pantry shelves, not the refrigerated aisle. They consider the eggs hermatically sealed inside their shell and safe for consumption.
So I would imagine they'd last even longer in a frig. But then, I'm not the one who's going to be eating it.
I have eaten 2-week old hard-boiled eggs (from my frig).