If the COB is producing SCR trigger pulses, and based on the PC606 being used, that's almost certainly what it does, you will have to drive a monstable circuit from each output and use the monostable output to drive the transistors. To be honest, without a specification or an oscilloscope to analyze the COB output, it is almost impossible to help you. a COB is not a specific device, it's a technology to mount silicon directly on a PCB to reduce packaging costs, what is actually in the silicon is anyones guess. Do you even know what the supply voltage requirements of the COB are?
Brian.