form serializing not working for file type inputs; need unminified code to debug

I realize this is probably not the best place to ask this but I have no other avenues.

Per Google's HTML Service documentation:

If you call a server function with a form element as a parameter, the form becomes a single object with field names as keys and field values as values. The values are all converted to strings, except for the contents of file-input fields, which become Blob objects.

The relevant line in the code is:

function handleFormSubmit(formObject) {
    google.script.run.withSuccessHandler(updateUrl).processForm(formObject);
  }

And:

<form id="myForm" onsubmit="handleFormSubmit(this)">
  <input name="myFile" type="file" />
  <input type="submit" value="Submit" />
</form>

The issue is that in our organization (we use G-Suite) the call fails with this JavaScript error:

Exception: Invalid argument: blob

It is failing when trying to upload/serialize the file into a blob.

I know our organization is doing SOMETHING that is preventing the file from being uploaded/serialized. My challenge is that because I cannot find an unminified version of Google's code that is responsible for serializing/uploading the file, I cannot debug the root cause so I cannot identify what the SOMETHING our company is doing so I can talk to the relevant teams to fix.

I did some debugging using Chrome's developer console and this is the closest I can find for where the error is being raised/thrown:

function be(a, b) {
    b = Error(b);
    b.name = a;
    return b
}

• a = "ScriptError"
• b = "Exception: Invalid argument: blob"

There is a post on SO on this and I opened an issue but I have not had luck with either:

• https://issuetracker.google.com/issues/141515596
• https://stackoverflow.com/questions/57577487/how-to-pass-file-upload-blob-from-html-form-to-server-side-apps-script/57975137#57975137

I am desperate to find a solution so I am hoping someone can either help me or point me in the right direction.

Expected Behavior

File should be uploaded, form data should be serialized, and sent to Google

Sample URL: https://github.com/gsuitedevs/apps-script-samples/blob/0ec9ff3bd109789668312cc2f0149f8187344b4f/ui/forms/index.html
Description:

Actual Behavior

JavaScript error:

Exception: Invalid argument: blob

Steps to Reproduce the Problem

1. Publish code as web-app
2. Go to web-app
3. Select file and submit

Start with the referenced samples/ui/forms/index.html and reproduce the web-app submission using the provided steps. Compare the observed "Exception: Invalid argument: blob" with the linked Google issue and Stack Overflow discussion; the report does not define a repository change or a verifiable completion condition.