Those rumours aren't true. That was in London.
According to The Athletic, the club allowed him to go to France on Wednesday to pick up his mother and come back on the same day. He came back on the next day. From what I understand, he didn't miss any training etc. There was other stuff about PCR tests as well.
The reaction from the club is harsh in my opinion and unnecessarily creates drama. Most clubs underplay things to make sure it doesn't create much damage, ours does the opposite...
Looking at how the club treated players that they wanted out in the past under this new management structure, I do think the fact he's on big wages and the fact they want to stop that being the case is a driving factor in this situation. Arteta also is a bit of a military minded manager when it comes to how he treats the players. Falls out with players regularly.