In my experience of situations like this (such as regulation failure in a SMPSU) its quite common for a small number of devices - sometimes as few as
1, to go S/C and "crowbar" the rail effectively protecting the remainder of devices. Occasionally a few devices will blow O/C instantaneously after going S/C, which can lead to further problems after the S/C devices are replaced - if the Vcc bond wire to the S/C die blows, the I/P & O/P pins cn the S/C die can load the O/Ps of other chips connected to it, this can be tedious to trace on bussed logic, its possible to snip the tops of DIL chip pins to isolate the chip while leaving enough pin on the chip body to solder the pin back on to (you can always replace the chip later if you want to) with the pin isolated you can use a pulse injector and scope to find if the snipped chip or something else on the bus line is still holding it down.