Maybe it's just me, but i tried your link and nothing. Can't help you.

The link worked OK for me.

Hard to tell if the roots are normal w/ all that soil still mixed in. Long roots aren't necessarily indicative of anything. The length of the roots aren't key, it's their condition. From here, I can't tell if they're dry & crunchy, or still OK.

As to that soggy water damage, that needs to be cut off immediately, before it has a chance to spread. Also, given that, I'd cut back to healthy growth, let it callous a day or 2 & then repot it DRY. I'd withhold water for a week after that at least, before watering it again.

Thanks for advice, Pirate Girl. I've already cut back the damaged growth and now I'll have to wait and see what happens.

Good to hear you've gotten to it already. Good luck, here's hoping it'll be fine (am guessing it will be).