Meredith was literally retconning entire segments of last season regarding Jen's arrest (saying she wasn't gloating, saying she didn't talk about it, not actually committing to her convictions once Jen pled guilty, etc.). Lisa was staying on her neck about it because she refused to take an ounce of accountability. The only concession I will give her for Part 2 is that I'm sure Jen's suicide attempt did ring particularly close to home for her so I can imagine she had more grace in the tank than anyone else on the cast.
I generally really like Meredith but her tendency to expect everything she does be retroactively taken in good faith is so frustrating and leads to zero payoff when the season concludes. She was great in Part 1 but fumbled nearly as bad as Heather in Part 2. Speaking of, Heather had one of the absolute worst reunion performances I've ever seen and Andy's soft ball questions made it even more annoying to watch.
Whitney started to come alive a bit in this one, I appreciated her immediately questioning whether the Harringtons giving money to Jen was the reason the Instagram drama went away so quickly. Also that final dig at Heather regarding what they regretted about the season not being their relationship. Overall Lisa was the only one of the four of them who had a good season and the only one who fully delivered on the reunion. It was at least satisfying to see the turnaround after last year!