I think what they meant by end is that time appears to stop at the event horizon for outside observers. As something approaches a black hole event horizon, time appears to infinitely slow, for an outside observer, such that a frozen image of the object gets stuck on the event horizon. But this image can't be seen because it gets infinitely red shifted such that no detection device can keep up with the longer and longer wavelengths.

You can measure time dilation at different distances from black hole, then extrapolate and see that time dilation goes to infinity at the event horizon.

> Is it even possible to empirically validate such a thing?

I wouldn't think so because empiricism implies experience which implies time

only for outside observers... you can validate it if you go in :)