PowerShell 7 - Invoke-WebRequest - use form parameter to send byte array as file

Question

My Powershell 7 script reads JPG files from a content service.

$fetch = @{
   Uri = 'https://content.site/media?id=82348'
   Method = GET
}
$fetchResponse = Invoke-WebRequest @fetch 

Image data loads into $fetchResponse.content as a byte array. Now I must send to a local web server.

$ingest = @{
   Uri = 'https:\\internal.site\ingest'
   Method = POST
   Form = @{
      file = $fetchResponse.content
      id = '82348'
   }
}
$ingestResponse = Invoke-WebRequest @ingest

Sending the byte array directly as above does not work. Image data is not detected in the received form.

If I first save the image locally and then use Get-Item to point to the file, it is successful. I do not want to save the images locally if avoidable.

Does the byte array need to be converted to another format to use the form parameter in Invoke-WebRequest?

Edit: after a bit of circular questioning and answering in the comments, maybe the question is better asked as, "How do I convert a variable's byte array to System.IO.FileInfo without having to write a file to disk?"