I beg to disagree. Plenty of stuff happened, it may not be dramatic, but making a home cooked meal is a big deal for Eric, and i really like Adam for immediately mentioning the nice smell. Eric didn't dismiss the comment, and i'm hoping he'll enjoy his first meal with friends at home. Having a neglected garden is the perfect topic for Rob to bring up next time he sees Eric. Maybe he can bring his laptop and show pictures in a better size than the phone.
I doubt Eric would be up to bringing Rob with him to a party, but it may depend on how it was sold to him. But if all the other guests are coming as couples or singles, then bringing a friend would be strange. And it would certainly be a lot to expect from Rob unless he had met Andy, Adam and Emily beforehand.