so I finally got past all those trolls (after 3 tries) and beat the big boss ... only to have the ending conversation over a weird camera pov and me still in control of the characters (can switch between them and run them around but only see them from the weird pov).
Then it just stays there, I can run around but do nothing to end the level.

Anyone else had this bug and got a solution? Is it just a glitch that might not happen next time?
(I'll try playing through it again but have no time for now so thought I'd check with others)

Ok, I did it again and this time it finished correctly - so turns out it was just a glitch.