Financial transactions ombudsman

Hi, would appreciate anyone that can show me in the right direction. Almost 2 years ago my wife had to receive a refund from a big corporation. Unfortunately they wrote wrong account holder (me instead of my wife) and as we could not go back to our country to fix things (she just moved to Switzerland at that time so she gave home bank account), our bank declined the transaction. We asked from them to send new transaction but they said they do not see the refund. As it is very big corporation I passed through multiple agents with no help from their side, just an answer they cannot help me and they did everything. They did not even share anything from their side about transaction so I had to investigate through our bank. I got official Swift recall with proof and I found their bank. Called them to try to make them check from their side because they need to reroute it probably but they just said I quote "we are multibillion institutional bank and we will not do such thing, we are sorry". Send them an email just to have a written proof but no response.

What can I do? In October it will be 2 years of this pending case. I will provide more details in pm to anyone that can help. The money in question is not so much to go to court and I dont know what (2k CHF), but I hope out of principle there is something I can do (especially when I heard that behavior of their bank when I can provide all evidence!)

I would really appreciate someone has some advice, at this point I am lost..

There must be some way forward without sacrificing money and court time in Switzerland..

Thanks!