The rest api requires Basic authentication. I would not have expected the query call to work. Try it with something like this instead:
$cred = Get-Credential
$Post = @('8aaa3f9e-ba13-425f-b662-069d06a17383', 'Interface', '5644', 'Testing ACK With API')
$Json = $Post | ConvertTo-Json
$Response = Invoke-RestMethod -Method Put -Uri $API_URL -ContentType "application/json" -Body $Json -Credential $cred
I tried that at as well. I may just stick with the powershell module for orion at this point.