Hi,
I have the same problem with Mac version of kmymoney. The latest versions which are available for download give the same error as above. I am currently using version 5.1.3-33a66be8aon on MacMini with M1 macOS Ventura and it is running fine. Unfortunately I do not have the installation package for it anywhere but I found a little bit older version Version 5.1.2-070754227 installation package from my backups, file name kmymoney-5.1-1082-macos-64-clang.dmg. It is for Intel hw based macs but I installed it and seems to work ok (not tested thoroughly) with my M1 MacMini. Only thing I had to do to get it running was to allow it to run from system settings. If somebody wants to try it I can share it (of course with no guarantees whatsoever).
hh