The distance Grigg was from goal doesn’t really matter - it’s whether he’d have been able to jump high enough. From the view I’ve seen I think there’s enough doubt that the cross was too high for Grigg to get to. If the ref thought that then it’s a caution - not saying he was right, but that would have been his thinking & not coz he bottled it.
Likewise for their pen - I’ve said I know how it looks but it’s not the Forest players who will have changed his mind but (coz his view was obscured) the asst telling him it was a foul as he’s asking the Forest players to back away. It wasn’t the Forest players changing his mind
Having been one myself I know how the officials work and what the ref’s body language & movement is indicating. As I’ve said it looks poor coz he didn’t get the players to back off & didn’t go over to the asst to show he was consulting him (although they speak through their headsets), but again he’s not bottled it. He (& his asst) may have got the decision wrong but they’ve not allowed anyone to influence anything or bottled it