They’ve apologised for the mistaken edit, but not for the programme. They’ve denied, rightly in my opinion, that it could have caused him harm, as he won the election. They have also denied any responsibility because the programme wasn’t broadcast by them in the USA.
So absolutely no admission of guilt. Quite the opposite in fact. A polite but firm denial.
They haven’t made it worse at all. They have boxed Trump in. If he proceeds now, with what will look like a hopeless but vindictive claim, he will just look more like the grifter he is.