Automator or Applescript to extract URL from email

Hello. I’ve been browsing this community for a while and this is my first dive into automation – long time reader, first time writer (who has searched!).

I am using Automator to run a workflow that consists of:

  1. Get New Mail
  2. Find Mail Messages (filter by unread and subject line)
  3. Applescript that seems to output the RAW email message

I am having issues with next steps, aiming to:
4. Search the RAW email message and download the first URL (“https://*.csv”)
5. Save the CSV file to a folder
6. Create a new email, attach the CSV, and send the email
7. Delete the CSV

I’m stuck on Step 4, and Automator’s built-in “Extract data from text” unfortunately did not do the trick. I can successfully get the RAW email output, which looks like the code below, but I cannot figure out how to extract the URL:
[format]{class:message, mailbox:mailbox “[Gmail]/All Mail” of account id
… misc. email headers …
… HTML …
Download URL:
… More HTML …
Download URL: (same link repeated)

Here is a screenshot of my workflow to-date:

Here is the Applescript I have in Step 3 that outputs the RAW email message:

-- This script accepts an input which is a list of message objects from Mail and returns their properties.
-- The properties returned are in the form of an AppleScript properties record.
on run {input, parameters}
	tell application "Mail"
		set output to {}
		repeat with thisMessage in input
			set output to output & (properties of thisMessage)
		end repeat
	end tell
	return output
end run

Thanks in advance!