Changing language settings from de_de@EURO to de_DE.UTF-8 results in UMLAUT errors in ERP FORM MASKS and OUTPUTS

I ran into a kind of bigger problem. In my company we have an In-house ERP-server (SUSE ENTERPRISE). I wanted to write a bash script that adds users automatically. However, I needed the signs "\" (=ALT+"\") and {} (=ALT + "{" or "}" respectively) in order to write that script. The enterprise linux did not support ANY SIGN that require ALT + sign combinations. So I was pretty sure, if I changed the keyboard settings from "de_de@EURO" to "de_DE.UTF-8" I would be able to solve this issue. By entering yast2(graphical settings manager) in the command line and changing the keyboard system setting this way, I did not fully solve the issue with the missing characters that come with ALT key combinations but I got half way there because it gave me the option to use ALT+NUMBER combinations inside the VIM editor at least. This way I could at least finish my bash script. I left the system keyboard settings like this because I thought I made an improvement anyway. But today, the company we purchased the ERP system from claimed that all GERMAN UMLAUTE were corrupt or failed to be parsed correctly, all UMLAUTE WERE MISSING they said. So they decided (without letting us know) that there was an error in our ERP linux server (because I changed something) and changed everything back to work again and claimed they needed an entire working day for fixing it (8 hours). 8 hours - 135 Euros each. Now my boss asked me who did the change and I admitted that it was me and this is why I am here. I offered him that I would pay the full price so the company does not need to pay for my mistake if it was. And that I would never touch this system again. However, I am pretty confident with Linux and I cannot seem to understand how someone needs 8 hours to fix a system keyboard setting that should 1. be found in a change log file 2. be fixed by entering yast2 to open the suse manager and change back the keyboard settings to the original settings and 3. I don't even believe that de_DE.UTF-8 should have any problems with recognizing GERMAN UMLAUTE. What is your opinion about this? Is it really possible that changing this keyboard setting messes up an entire ERP (the forms and the output)? Or are they trying to charge us a service that was fixed in like half an hour and make 8 hours out of it? And is it normal that a company that sells a Linux SUSE enterprise server is incapable of making sure that ALT+CHARACTERS are recognized OUT OF THE BOX? Don't get me wrong. I realize that I should not have touched and changed a running/productive server without asking anyone but I believe that the deal/problem/issue is not that big to charge that big of an amount for this service. I have a 3 years experience with Linux Debian. So SUSE is nothing too new for me. I would like to know your expertise opinion about this. I would also like to know how I should act in this situation as an advice because possibly - even if I pay the full price - I might still get fired for that action. I am very open to criticism and I am not afraid of indoctrinations - on the contrary - I ask for them.