Using SSM to run powershell script which exists on server fails

Question

We have scripts on a server in the following directory:
C:\Program Files\My Company\Product Scripts\do_a_thing.ps1

Using AWS-RunPowerShellScript for the Command Document. AWS Console says that the command runs successfully, but I can tell that it is not. 
Combinations I have tried:

Commands textbox:
do_a_thing.ps1
Working Directory:
C:\Program Files\My Company\Product Scripts

When I look at the Output screen:
Output
Output(0)
Error:
do_a_thing.ps1: The term do_a_thing.ps1 is not recognized as the name of a cmdlet, function......

If I try to put the whole path into the "Commands" textbox, without quote
Error is:
C:\Program : The term C:\Program is not recognized....

If I put the entire path to script in quotes, Output shows the full path to script, but not the actual output from running the script
Commands:
"C:\Program Files\My Company\Product Scripts\do_a_thing.ps1"
Output: 
"C:\Program Files\My Company\Product Scripts\do_a_thing.ps1"
Error:
Blank

What is the correct format to get this to run properly?

Answer

After about 2 or 3 hours of trying to get this to work, I was able to see it run correctly with:
Commands:
& "C:\Program Files\My Company\Product Scripts\do_a_thing.ps1"
Working Directory:
"C:\Program Files\My Company\Product Scripts"

I am curious as to whether SSM will consider the Status "Success" if the script fails for some reason. It was marking it as Success before when it definitely was not running the script at all.

Using SSM to run powershell script which exists on server fails

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