You are the real MVP @Lux. chantools solved the problem. For anyone from the future having a similar problem, the command I used was:
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Footnotes

  1. No point hiding the address I sweep to as I exposed the origin address on the post anyway.
  2. As for the general usage, I exported both AEZEED_MNEMONIC and AEZEED_PASSPHRASE as environment variables, so I didn't have to pass it on each command.
  3. I manually published the transaction showed in that screenshot, but one could also append the --publish flag to publish it right through the CLI.