I was curious about what happened since the write-up ends abruptly before revealing the testing results.

Wikisimpsons has a bit more info sourced from DVD commentary revealing that the tomacco had no nicotine in it: https://simpsonswiki.com/wiki/Tomacco#Behind_the_Laughter

Wikidoc has even more detail but no sources: https://wikidoc.org/index.php/Tomacco