Most of the high-power enlargers I've seen have a built-in contactor to switch the lamps on and off. This contactor is then driven by the timer. I would be surprised if your friend's Omega does not have something similar. Presumably there is a power supply of some sort with the enlarger? This is likely to include the necessary control circuitry for use with a timer. I'm afraid I am not familiar with Omega enlargers as they are rare in the UK.
If not, he will need to obtain a high-power relay or contactor with a mains-voltage coil, connect the coil to the Analyser's Enlarger socket and connect the enlarger lamps to the relay contacts. It is not possible for us to increase the switching capacity of the Analyser above 500W.
Hope that helps.