I'd definitely like to see more research into topics such as this. Gut health definitely has an impact on the brain, but the headline is a big stretch and looking for clicks. Never trust media corps with science news.
I have dietary track issues myself and only poop ~1-3 times per week. At my worst I went about 2 weeks between poos. I also have adhd. It is clear this research is 100% true.
I think your data point disproves the original claim, which was more pooping == ADHD. Given your data point disproves the claim, I say we ignore it. Science. :D