Two hands pushing down looked clear enough to me. If I'm looking to give them a sniff of a way out perhaps they thought the lurch forward from the defender is a bit too dramatic. However, that's a stretch and anywhere else on the pitch it's a foul all day long
The Toon winner should have been chalked off for the one clear issue which was the push on the defender.
However, I wont shed too many tears for Arteta as Havertz should have got red. Nasty leg breaker tackle if he connects with the studs up front foot. Lucky for him it's only his trailing foot...