When you find it, would you please ping me? I don't have a Latin dictionary, but that is a great idea!
Our choices are--
Misohomosexualist Mishomosexualist Homosexmisia
...or some variation thereof. None of them are 'smooth-sounding', if you get my drift--they sound choppy and made-up. I'm partial to misohomosexualist, but if you come up with something that sounds better, let me know.