I've been a longtime fan of Obsidian and have alway supported them. They're an inspiration when it comes to making roleplaying games. The marvels they manage to put out are one of a kind - and Pillars of Eternity is no different. It's a real shame that this select little group has set their sights on one of my favorite companies in an effort to try and tarnish their creation.
The little rhyme is entirely fictional and focuses on the endeavours of a fictional character. This fictional character chose to resort to extremities because he was obviously a bit dim. The world of Pillars of Eternity is expansive and it has room for all sorts of characters, including that particular one. If you think it's offensive, that's alright. The fictional character might've been a bigot to you, an idiot, and someone to be pitied. There are two things he is not. He is not real and he is not Obsidian.
In rich worlds there'll be many types of characters. A portion of them may appear funny to some but offensive/unfunny to others. It's precisely because of the variety of characters that conflict sparks in these games, the world becomes layered and draws out more emotions from whoever has the luxury of experiencing it. To put it simply, you won't like every fictional character and some fictional characters are meant to be despised.
It's a pity that these days controversy emerges because someone deems a fictional character offensive. Can you not take it for what it is? A poor man who thought it necessary to jump off a cliff after mistakingly sleeping with another man. Perceive the situation as funny, boring, pitiful and whatever else have you. You are allowed to be offended too, if you must. But realize that these are the actions of the fictional man which offend you and not Obsidian.