The problem in Sodom wasn't that men were banging men, strictly speaking. It was that the society was run by men, but social status was determined by who was banging whom. Homosexuality wasn't the problem, the problem was that their entire political structure was based on sexual favours and dominance, instead of at least vaguely sensible things like strength, wealth, or merit.
So, if the word 'sodomy' is used to describe 'what brought about the downfall of Sodom' rather than overgeneralized to include all sex between men, regardless of whether their relationship is ethical or not, then it is necessary for Neplesia to forbid it, for the same reason why corporations need to make sure that hiring decisions and promotions aren't based on sexual relations around the office. It doesn't matter whether members of an organization are male, female, both, or neither; using sex to decide how to run a group runs that group into the ground... and not in a fun way, either!
I think they're capable of getting over the assumption that only men should be in power, so that they can look at the ethics of it, instead of making the huge 'correlation = causality' mistake we're all too familiar with.