Assign AppInsight Application via API failing with no errors

Hello all,

I have been working on a script to assign AppInsight for SQL to nodes using the API. There was a great starter script on the GitHub but I'm running into a strange issue. When running the script I'm getting it to fully execute but it will only execute with a result of -1 regardless of setting the duplication flag as true or false. Nothing shows up in the SWIS logs nor the APM businesslayer logs to help me investigate this. I was even trying to change up how some of the script was putting the info together just in case it was a weird formatting bug but I've not come to any conclusions on that. Where should I look next?

Import-Module SwisPowerShell

$username = "REMOVED"
$SecurePassword = ConvertTo-SecureString -AsPlainText -Force -String "REMOVED"
$cred = New-Object -typename System.Management.Automation.PSCredential -argumentlist $username, $Securepassword
$hostname = "REMOVED"
$swis = Connect-Swis -host $hostname -cred $Cred

<#
$appSettings = @{};
#$appSettings.Add('InstanceName', ''); #instance name is not required, if not specified than default instance name will be used
$appSettings.Add('PortType', 'default');  #default or static, when static than PortNumber needs to be set
$appSettings.Add('PortNumber', '1433');
#>

$appSettings = @{

    #InstanceName = ''
    PortType = 'default'
    #PortNumber = '1433'

}

$swis = Connect-Swis -host $hostname -cred $cred

$nodeId = 13542
$credentialSetId = 50 #-3 means take it from node
$template = "AppInsight for SQL"
$applicationTemplateId = Get-SwisData $swis "SELECT ApplicationTemplateID FROM Orion.APM.ApplicationTemplate WHERE Name=@template" @{ template = $template }


if (!$applicationTemplateId) {
	Write-Host "Can't find template with name '$template'."
	exit 1
}

Write-Host "Creating application on node '$nodeId' using template '$applicationTemplateId' and credential '$credentialSetId'."

$applicationId = (Invoke-SwisVerb $swis "Orion.APM.Application" "CreateApplication" @(
    $nodeId,
    $applicationTemplateId,
    $credentialSetId,
    "true",
	$appSettings
)).InnerText

# Check if the application was created
if ($applicationId -eq -1) {
	Write-Host "Application wasn't created. Likely the template is already assigned to node and the skipping of duplications are set to 'true'."
	#exit 1
}
else {
	Write-Host "Application created with ID '$applicationId'."
}

Maybe tdanner or KMSigma.SWI might have answered this many times and I can't google to for the life of me ;)