Upstairs neighbors smoking in non-smoking building + frequent fights that may be physical — afraid to call police due to shared entry

I live in an apartment building with shared entrances. I recently got new upstairs neighbors, and since they moved in there have been two ongoing issues:

1. Smoking in a non-smoking building. The smell (weed) comes directly into my unit, often late at night. It’s been happening consistently, not just once or twice, and I'm afraid it is starting to stain my belongings with the smell. We have a no smoking policy in the building and management has "reminded" them of this rule.
2. Frequent loud arguments. They argue loudly on a regular basis, and last night it sounded like it got physical (loud crashing, yelling about getting hit or being the aggressor, and crying for an extended period of time). I was genuinely worried someone was being hurt. I have some audio recordings of what they were arguing about since you could hear it in the hallway, but I wasn't able to get any of the hitting on recording since it happened every time I stopped recording. This is the first time I have ever heard anyone argue like this in my life.

Here’s where I’m stuck:
Because we have a shared front door, if I call the police for a noise complaint or welfare check, the officers would likely need to be let in by me, which would make it obvious who called. I’m worried about retaliation or escalation if that happens.

I have already notified my landlord about the smoke and the fighting, but I haven’t seen meaningful action yet.

My questions are:

• At what point is it considered appropriate or necessary to call the police for suspected domestic violence if I don’t have visual proof?
• Is there any way to request a welfare check anonymously in this type of setup?
• What is my landlord legally required to do when tenants are violating a non-smoking lease and possibly creating a dangerous situation?
• What steps can I take to protect myself if I do report this?

I’m not trying to get anyone in trouble — I’m genuinely concerned about safety, and I don’t feel comfortable in my own apartment right now.