The first, and most obvious error was way too much freshly minced rosemary. I always tell people to be super-careful about adding this resinous herb. I wasn’t paying attention, and just added what I had chopped without thinking, and it was pretty much all over at that point.
Adding cream helped nothing, and only made the herbaceous reduction more caloric and offensive. I probably could have added some lemon, mustard, horseradish, or other heavy-hitting condiment, but by that time nothing was going to unrosemary this train wreck.
On the bright side, the grapes were really good, and even after 30 minutes in the oven, had a juicy, still-firm texture. Their warm sweetness went very well with the meat. So, I hope you watch, critique, and maybe adapt this potentially amazing recipe into something worthwhile. Enjoy!