(This is mostly a copy of a question I asked over at Law.SE. I'm reposting it here following the advice of a commenter to look for solutions with a more interpersonal appraoch.)
I have a friend who lives in the Netherlands, let's call her Allison. Both her and her neighbor (let's call him Bob) live in an apartment complex owned by a therapy organization they are both patients at, and their landlord is also the owner of said organization. Bob has lived there longer than Allison.
Every once in a while (at least once a week, though sometimes a lot more often), Bob tends to be very noisy in his apartment, by listening to loud music or playing with a pinball machine (a physical, real life one, not a video game). This often also happens very late at night, which is obviously not allowed per contract, and the walls are incredibly thin. Allison has complained about this numerous times, as it prevents her from sleeping at night and her mental health is suffering because of it, which the therapy home was supposed to be helping with. The inhabitants of the other apartments don't hear any noise, as Allison's apartment is the only one that share's a wall with Bob's.
The problem: Since Bob is a therapy patient himself, the landlord and the therapists appear to be protective of him. Supposedly, he has his own baggage that prevents him from noticing, caring or remembering that he's being inconsiderate. While they don't explicitly condone him doing this at night, they barely take any direct action. Instead, they advised Allison to use earplugs, since the person who lived in her apartment before her never complained about this and they figured she may just be too sensitive. When the earplugs didn't help, they told her to message Bob whenever he's being too loud, because he apparently needs constant reminding that he's not supposed to do this after a certain time of day. Allison tried this, and it helped, but the silence usually only persists for a few minutes before being broken again.
On Allison's request, the landlord eventually agreed to order noise cancelling panels to be installed on the wall between their apartments. However, he only agreed to pay for the very cheapest ones available, which had to be shipped from China and are now being withheld due to the Corona virus. Furthermore, after it was clarified that these panels would need to be installed on Bob's side of the wall in order to have any effect, Bob suddenly expressed that he's not willing to put in the effort to do so. In other words, he refuses to actively do something to fix the problem he's causing, despite the panels being gifted to him (Allison has expressed willingness to invest into panels for her side of the wall out of her own pocket, just for added sound isolation, but as stated earlier, those won't do much on their own).
Recently, Allison's therapist started encouraging her to look for other apartments, all of which turned out to be substantially more expensive than her current one (given similar size and quality). Despite knowing that Allison's financial situation isn't the best, her therapist kept suggesting that it might be worth it to get some peaceful nights. Allison feels like this is rather unfair, like she's being punished for her neighbor breaking the contract and keeping her up at night, and that the landlord / therapy organization should put more effort into solving this for her, as the contract states that excessive noise at night is grounds for eviction. However, whenever she brings these arguments up, they keep getting dodged.
Allison tried contacting the police about this, but they dismissed her case as something that's out of their reach. They advised her to try something called a "neighborhood mediation", though Allison has strong doubts about the usefulness of such a thing, as the landlord and therapists have already tried mediating between the two of them.
Question: Is there any other way to resolve this issue? As far as I can tell, Allison and Bob are not at all on good terms, for obvious reasons. How could one go about getting the landlord and the therapists to take Allison and the problems this is causing her (sleep deprivation, nausea etc) seriously?