This is a possible reason why it's working for Eridu and not others. Having the frog in person can provide many visual clues and multi-angled views, hence greatly improving the chance of accurate sexing.
For example, I can sex Central American cichlids in a tank when quite young; but it's a guessing game from a 2 dimensional pic with no venting, fish movement or interaction among them.
If a super-female like Eridu states, and fertile, OP's got quite a treasure. Would wait to see if Griff's male grows to maybe 9-10 in. and formulate a plan to cross them. He, he, he, just dreaming of a selectively bred 14 in. GABF in couple generations

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