(Update to entry immediately below.)
The most senior (and influential with executive management) proposal manager and I had a back-and-forth in which she essentially argued for the "grammatically correct but inconsistent appearing" approach and I repeated my recommendation.
She wrote, in part, "I say we talk about it next week and make a decision that we can work with."
For twenty months I have been told repeatedly, "You're the editor. You decide." Most of my style recommendations has been rejected for reasons that have nothing to do with style rules or logic. In total, those rejections have rendered completely meaningless, my role as the "gatekeeper of style."
That resistance and unwillingness to grant me the authority that should go with my responsibility, flows almost completely from the inability of the proposal center manager to tell our stakeholders in no uncertain terms that the editor who has twenty-six years of experience will make decisions of this kind.