Nope. That’s just a shitty article. Here you can read that 1) what they compared was not T-rex’s DNA, it was collagen and 2) the results confirmed the closest relatives to dinosaurs were birds in general, not chicken.
By the way, dinosaur DNA might indeed have already been found (in a hadrosaurid called Hypacrosaurus), but it’s not entirely sure yet.
Is it really chickens specifically that are the closest relative, not any other bird?
Yep
Nope. That’s just a shitty article. Here you can read that 1) what they compared was not T-rex’s DNA, it was collagen and 2) the results confirmed the closest relatives to dinosaurs were birds in general, not chicken. By the way, dinosaur DNA might indeed have already been found (in a hadrosaurid called Hypacrosaurus), but it’s not entirely sure yet.
So it’s inclusive of ostriches and not exclusive of chickens, so what I said was entirely correct just incomplete.
Technically yes. You forgot to include all other birds. Chicken and ostriches are mentioned at the beginning of the article as examples of birds.