Did manual testing after seeing that lava-test-case uses eval. The execution of the command through eval ended quite quickly, and when I checked the exit code it was 255. I don't think there is an alternative to using eval, except maybe a subshell through echo? e.g. echo $(cmd)? But that wouldn't return the exit code for the command would it? I know eval is used because it allows the running of the command passed as an argument, and then being able to see the exit code to determine if the command worked or not.
I did do a manual run of echo $(cmd), and it ran for around the expected time, and the command did work. The only problem thereafter is knowing how to determine if it was a fail or success using the existing infrastructure. Will do some testing in the meantime with echo and subshells to see what I can do.
Best regards, Michael