Good morning Niels
I originally answered in german as you are german and i wanted to make sure that i dont mess up with wrong english expressions as i think it is important.
1. a normal streetview trusted tour are the 360 degree tours that are displayed in the GBP. As Google provides a link with them, they can be placed in a website. An interactive tour is an enhanced streetview tour. Go to the Gothru website, there you get all the explanations about it and yes thats what is used on the zero zero website.
2. i did not check the local organic ranking, i am not payed for any managed services therefore i only check from time to time the local scans and answer his reviews.
3. as written, he got 20 about more reviews since then. BUT it is very important to know, also as already written

that there have been interactive tours since 2017 both for Baden and Zürich. Both in one website and linked with the respective profile. Both on top of the website. In decembre 2020 we made a new website with only one interactive tour from Baden. The streetview tour from Zürich is since then also on the website but not on top but in the "how to find us" part. Here i see the same as with Buchhandlung Klosterplatz.
As stated, due to this ones incorrect accusations, I will now leave the name of Baden as he changed it. This will show if this really gives a downgrade in the placement. BTW no change at all by now^^ since the removal of CD & Vinyl as legit part of his company name. TBH it would have surprised me IF it really had any impact as the keyword "Plattenladen" is in question here. By the same time, as soon as the new sites with an interactive tour on top for each, linked with each profile, will show if the changement for Zürich helps to rank better. But this will need some time, therefore i am sorry i can not answer right now. I almost forgot the original post has only the actual scan, i dont have old ones from zero zero.
But what is very important in my initial post is the extreme difference of views of photo's (GBP statistic) against his competition as well as the situation that those are all coming from the tour and are stated as "pictures from customers"!
In one of my replies i posted the actual scan as well as the start of coiffure-ume. But here we have to situation that here name (as registered in the swiss traderegistery) has the keyword extensions in it. Therefore this is to take with caution. It just shows that she climbed up from nowhere to the top in a period of one year against about 260 results in and around Zürich. But also here many other salons have extensions in their GBP....if legit or not is another question