wev kept them free range for 6 years but they never bred, never found eggs either, got new trio last year but they still roost in trees every night as far as i can tell.
the farmer previous to us had guineas and they were freerange and always coming back with a brood keets in the spring.
if u were serious about breeding them i would presume ud need to contain them in some manner to get their eggs and incubate them?