Well since there's no "pregnancy" test for snakes that I know of it's basically an educated guess. He may have palpitated and felt eggs, he may have ultrasounded the snake (not likely but some big guys do have a machine) but nobody can guarantee a good egg outcome as far as I am concerned. She may well lay nothing but slugs or she may lay a whole clutch of perfect eggs. When you buy a gravid WC it makes the dice roll of breeding all that more chancey.
yes i understand that but i have a email where he says i guarantee theyll be gravid...so if she ends up not being gravid, i could get my money back and keep my wonderful snake? maybe get him to send me few nice hatchlings of what they kept??