Cotoneaster (as a generic group) was the first thing I thought of, but when I looked for reference pictures I could not find a specific one with the right twig configuration.
Also, the two or three Cotoneaster that I know have much darker and smoother main trunk bark. At this time of year they also tend to be covered in berries, which appear to be absent from the pictured tree.
I think it might be Crack Willow, which would explain the rot in the centre rather well, since they are prone to it.
Where did the better half find this piece of mystery wood?