Old gear - if you did not leave it powered up for 20 minutes or so without popping it, it probably would not have failed. Electrolytic capacitors depend on their use of a thin film that forms when they are under powered conditions, and gradually dissolves when they are not powered up for quite a while.
You may have had the blown cap spray bits of molten innards onto other components, causing them ill. Or you may have had an oscillator transistor or voltage doubler diode blow from over current.
The troubleshooting effort may outweigh the value of the flash pack.
The caps themselves are not impossible to swap out, but you do not sound like you are up to the task yourself, at first blush.