Here is the only answer that managed to work for my problem, got it figured out with the help of this webpage (nice reference).
powershell -command "& {&'some-command' someParam}"
Also, here is a neat way to do multiple commands:
powershell -command "& {&'some-command' someParam}"; "& {&'some-command' -SpecificArg someParam}"
For example, this is how I ran my 2 commands:
powershell -command "& {&'Import-Module' AppLocker}"; "& {&'Set-AppLockerPolicy' -XmlPolicy myXmlFilePath.xml}"