Enable connected to unpowered regulator on another board
Interpreting the "Absolute Maximum Ratings" section of datasheets as the maximum ratings that won't damage your device, it seems like the Micrel chip would break if the edge scenario you described happens. I think the Microchip IC is more promising, because what the maximum ratings reads like to me is that the pin is tolerant to 30V regardless of Vcc. 

With regards to the parameters, I think it's just defining the rules you'd want to follow for normal operation. Having a broken fuse would kind of imply that something's gone wrong, so now you're really just concerned about not breaking the chip.