Do you have an .env file present in your directory?
The .env.example is just that, an example.
You usually copy that to the .env file (on linux the command would be cp .env.example .env).

Also "AES-256-CBC" reqires a 32 character string as a key. If you have SomeRandomString as the default, it would make sense that it would fail. Either change the key to a 32 character string, or use "AES-128-CBC".

In testing this, both projects have only .env.example. With the source project all of the artisan commands complete successfully after a composer install but with my fork I have to copy .env.example to .env and place a 32 character string in the APP_KEY setting in order for the artisan commands to complete.

What would be the difference maker that allows the source project to complete, but my fork to fail the artisan commands?

Thanks for the help.