AWB got lucky with the Havertz one, but I think it was the right decision.
It looks like Havertz is already on his way down even before the contact is made. That is why it looked so soft in real time; he was looking for it all day long. If he had stayed upright and dived after the contact, it would still have been soft, but it would probably have stood because AWB would have been seen as the reason for him losing his footing. However, it was clear as day that he was tumbling over even before the minimal contact with AWB was made, probably because he was half-expecting the contact to come with AWB's leading leg rather than his trailing.
Hojlund, on the other hand...I just can't understand how that isn't a penalty. Gabriel has played the man and Hojlund, to his credit, has tried to stay on his feet and win the ball. He clearly hasn't dived, so what's the issue.