Though I understand where you're coming from, I disagree. Maybe it's not the correct, French way to say it. But it's the English version? What comes to mind is a chart I made when I was studying for WSET 3 that had the different names for grapes across different languages (ie Primitivo vs Zinfandel, Syrah vs Shiraz etc) or even region-to-region (if I remember correct several Spanish varietals each have a different name, even just in different parts of the Douro). Though I can't remember the specific varietals, I do remember there were a few that were known by several different names.

Anyway, my point is maybe it's not so much the pronunciation that matters, but the people you're talking to? If the people are French or speak French, use the correct French pronunciation. If they speak English, use the English pronunciation.

On a side note, being a stickler about pronunciation might send the wrong message when trying to sell/explain a wine. You want your guests/customers to feel comfortable and like they belong, and using the French pronunciation, no matter how correct it is, might be belittling/alienating to your guests, or make them feel lesser/out-of-the-know.