WMI is not accessible

From a PowerShell perspective (not directly LM), -Credential (Get-Credential) would prompt you for credentials. If LM is running that command, it probably wouldnt work. Because it would need to interact with the credential box. Instead, you would have to pass credentials to the command.

There are several different ways to do this. 

Here is a simple way to test: 

$scriptUser = "domain\testaccount"
$scriptPassword = "aPasswordForMyAccount"
$scriptPass = ConvertTo-SecureString -String $scriptPassword -AsPlainText -Force
$secureScriptCreds = [PSCredential]::new($scriptUser, $scriptPass) 

Get-WMIObject -Computername DC01.mydomain.com -Credential $secureScriptCreds -Query {select * from win32_operatingsystem} 

Note: I would not recommend storing plaintext credentials in your scripts. You might be able to pass them with a LogicMonitor property