Surprisingly, I somehow failed to notice this until yesterday. If it becomes an issue, I am not in any way attached to the name - i'd be happy to change it.
Not really, because it doesn't need to be a real word or an existing name. It could be Rexfus, for example. Even the dot com is available, and as a combination of Rex and Rufus, still dog inspired.
That was me trying to be clever choosing a quintessential dog name, as the application "fetches" the paper (rss feeds) for you :D . I was playing around with the name Rover and a few others for a while as well, but went with Rufus for the cheap .news TLD
I don't think it's an issue, but it'll be harder for your tool to be at the top of search engine results, so some rebranding might be beneficial for your visibility.
It's something that is bound to happen. There are a finite number of words, names, and spellings to make use of.