The person who calls it “nonsense” is a bean counter at Oxford, an accountant, also known as the bursar of New College.
As you probably know, Gregory comes from a long line of scientific greats in the Bateson family who have been dons at Cambridge for centuries. An unbroken chain.
Gregory’s father William first coined the term “genetics” after translating Mendel’s work from the original German.
The great scientific families of England, namely the Huxleys, the Darwins, the Batesons, the Whiteheads, and more conversed and socialized in elite circles unknown to bean counters on salary.
As a family deeply rooted in the scientific (and specifically biology) realms of discourse, it is more than plausible Gregory’s father and or grandfather heard this entomological tale first hand.