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No, just jumping the input should give you full output... Might need to up the cap in series with it to a 100nf, but you should be ok as is for testing.

I would try this:
-pull out the tl494 and tc4422
-Jump pins 5 and 6 in the tc4422 socket.
-jump pins 7 and 9 in the tl494 socket
-put an ammeter in series with the +12v of the circuit
-plug in the circuit.
*if you short out your supply pull out the transistors. If that solves it replace the shorted one. If it doesnt recheck you wiring.
-pull out the jumper from 5 and 6 in the tl494 and put it across 8/7
*you should see pretty much a dead short.
*if not then check the fets/diodes for being open and then for wiring problems
-Disconnect the primary of the transformer
*the short should disappear. If not check wiring errors...
-reattach the primary
-put the jumper on the tc4422 back to 5/6
-remove the jumper on the tl494 and put it across 8/9
*you should see a short
-remove the primary from the transformer
*the short should disappear.
-move the jumper back to pins 8/7 in the tc4422
-plug it in again
*you should see a dead short
-unplug the primary of the transformer
*there should still be a dead short.
-unplug the circuit
-put a neon bulb on the output of the transformer
-Plug the tc4422 back in.
-Plug the supply in
*it should show up as a short
-move the jumper from the tl494 back to 7/9
*it should still be a short, you should also see the neon bulb flash.

If you got that far the circuit is about 90% working. Just the 494 part is broken. If you just want sparks hook up a 555 running at about 15khz at a 50% duty cycle to pin 9 of the tl494. You should get hv out on the flyback

From there is just the tl494... triple double check you wiring, and try a new chip...

Good luck!