It appears that my former officemate Andreas Reinhart (University of Graz, Austria) has disproven the Ankeny-Artin-ChowlaAnkeny–Artin–Chowla conjecture: more precisely, Andreas has found that $$ d := 331914313984493$$ is a counterexample to the conjecture, see https://arxiv.org/abs/2410.21864A counterexample to the Conjecture of Ankeny, Artin and Chowla (especially Theorem 2.3) for further details. This is not exactly an answer to the OP, but seems relevant nonetheless.