Hi RadoK,
What is the voltage at at the point between the 470K, 1M resitors and the 220nF cap? Should be pretty high, 120-350V.
If you can disconect the "positive" cable that goes to the main caps. Leave the "negative" connected. If you can, solder a relay across the SCR and use a battery to activate the relay (just touch the wires quickly agains the battery to fire the trigger transformer). Wear some rubber gloves just in case and always wear eye protection when working with HV+caps/flash tubes.
Now with the main capacitors disconected (and discharged) trigger the trigger in a dark area and check to see if the xenon tube flashes with a light blue/violet glow. Basically this will show if the trigger coil is actually doing something or not.
If the trigger coil works then try it again with the main capacitors connected. If it refuses to fire then the flash tube is provably a higher voltage model (higher trigger voltage and maybe 480V for example).
I've built, repaired and modified numerous strobes, so i'd start there. Only try this if you believe you can do this safely. HV caps are very dangerous.