Man that's rough timing, but honestly I've never trusted those modern blower motors for heavy forging. My old hand crank blower from the 70s has never quit on me once, even during all day hammer-ins. Sometimes the simple gear just works better when you're pushing metal that hot. A seized motor in the middle of a commission is a nightmare though, hope you can get the axe back on track.
Wait, three days straight with a sledge and a striker? Your buddy must have arms like tree trunks after that. I can't even imagine the blisters, my hands hurt just thinking about it.
Remember my buddy who had his power hammer die halfway through a big order. He ended up finishing the last ten blades with a sledge and a striker, took three days straight. He swore off anything with a circuit board after that. Robin_Schmidt57 has a point about simple gear. Sometimes you just need a thing that turns when you turn it, no surprises. Watching my friend swing that sledge all weekend really makes you respect the old ways.