Seyon, who knows what happened - but you should simply chalk it up to experience and move on.
Only our own actions are under our control

so it is best to concentrate on those, and work on how to present one's self the next time around to avoid a similar disappointment.
Getting angry is never helpful or effective, and can often put you in a bad light. While disappointment is understandable, you should avoid being seen to react this way.
If it's any help, here is what I do when I approach a rescue:
First, my German isn't perfect - and is weakest over the phone. So rather than calling I first write an e-mail. This way I get a chance to say everything I want to say. I am convinced that writing first steers the conversation in the direction I want it to go, and makes a good first impression.
I start out by introducing myself and giving an outline of my skills and experience, highlighting my experience with rescue animals and my committment to the rescue ethos.
I talk about my motivation, why this particular animal has touched my heart.
I talk about the kind of life I can give the animal, addressing each and every point in the animal's dossier. I show
in detail how I can meet each point in the adoption criteria - or where I cannot, I address that and I propose what I believe to be acceptable alternative.
Describe your accomodation with an eye to meeting the animal's needs and the animal's safety. Be specific. If you are renting, mention that you have permission to keep an animal already written into your contract.
And when looking for a cat, address the indoor/outdoor issue. Understand where the rescue sits on this point.
I mention that my vets and trainers would be happy to provide references.
I then propose a follow-up phone call, and ask when that would be convenient. (From my own rescue work, this is important. Rescue volunteers are usually very busy - and you want to catch the volunteer at a time when he/she is not so frazzled.)
Then I ask a native speaker to proof read my note.
When I follow through with a phone call, it will be obvious that I am an Auslander. So I use that to my advantage. I talk about how my dogs have traveled the world with me, highlighting my commitment to their welfare no matter where life takes me.
Let's face it - this is a real concern for many rescues. Unfortunately the bad eggs who have abandoned their pets when opportunity calls elsewhere have given expats a bad name. Working in rescue myself, I see folks dumping their pets when leaving the country all too often - in every stereotype there is a kernel of truth. So we need to be proactive, address this concern head-on. Show the rescue that you have a plan in place should you find that leaving Switzerland is in the cards.
ETA:
Another 'Auslander' issue that is important to address: One needs to show that one understands Swiss expectations of what it means to give an animal an 'artgerecht' life, which may be different than what is expected - or percieved to be expected

- in one's home country. Toward that end, the BVet's brochure 'Katzen Richtig Halten' is helpful background material.
During the phone call, re-iterate all the points you mentioned in your note. Also ask questions - about the rescue, about the animal in question. Make it personal.
Propose an in-person meeting.
Remember that this is an assessment on both sides. The chemistry between the rescue, the animal, and you needs to be right.
Bottom line, treat every contact as an opportunity to put yourself in the best light possible. I'll say it again: be proactive.
If after all this the rescue decides that you are not right for this particular animal - accept their judgement and move on.
Every rescue works with it's own guidelines. Some are very strict, some quite flexible. That you haven't 'clicked' with a particular rescue (or animal) does not mean that rescue is not for you, simply that you need to find another - and there are so many rescues, so many cats in need.
You'll find your feline friend, don't worry.
All the best.