Actually .... I think the roaches will end up taking over and will likely eat the crickets .
I found this out by accident once , a domestic roach found it's way into bin I was using the time to keep my crickets in (it was a lot larger than the crickets) and it made a meal of the crickets.
hobbyist breeders I know who have woodie and cricket colonies all keep the woodies and crickets separated. Some even have insect breeding tub racks in their reptile sheds or reptile rooms.