Before you spend another $200.00 each, check out the link below and look at the pictures. I think what you had was Pixicephalus adspersus--African bullfrog. Conraua goliath are not exported to the pet trade as there is a limited number of legal exports (300) each year and there is a waiting list of 2 or more years. They go to zoos, wildlife preserves that spend thousands of dollars in an attempt to simulate their habitat--cascading water falls, large pools. Even so, they do not do well in captivity. Neither have they ever been successfully captive bred. If it were possible for someone like you to keep, breed and raise them at home, they would already be common in the pet trade and inexpensive. This is economic logic.
Exporters list both Conraua goliath and Pixicephalus under the common name of bullfrog, so a mix-up in labeling could have occurred that might not be the fault of the pet store, but should have been the responsibility of the importer and distributor to catch. By the way, the wholesale export price of an African bullfrog (Pixicephalus) is $1.28 apiece.
Pixicephalus
-----
Patty
Lost River, Idaho
D. auratus blue
D. galactonotus
D. imitator
D. leukomelas
D. pumilio Bastimentos (soon)