if I have the two files. Maybe it's a problem with Elementary OS, or I don't know.
I also tried to open it from itch.io launcher and it gave me the same error.
It could be I suppose, I don't know how Elementary differs from Ubuntu. It's interesting that the itch app also has the same problem, and it does hint at a problem at the OS level. My googling turned up a thread about somebody trying to run another application on Elementary and having the same problem, even though the files were definitely there in that case as well: https://forum.teamspeak.com/threads/109455-Elementary-OS-bash-ts3client_linux_x8...
Unfortunately that was unresolved, and I haven't seen anything else that might explain what's going on. I will see if I can install Elementary in a virtual machine and reproduce the problem.
I assume you have not had this issue with other games?
I think I've figured it out - I think it is because 32 bit applications are not supported by default in Elementary. It's probably the same in Ubuntu but I think I added all the 32-bit libraries because I needed them for something, so that is why it is working for me.
I will try to do a 64-bit build for you and hopefully that will work!