Weathered Monument 95%

Hey, this seems a common problem and after exploring the subreddit - I still can’t get this last bit done. Stuck on 95% on weathered monument!

I have opened all the chests (and went back to each one just in case). I have got both secrets (one from behind the fan and one from the cave above the first ice slide).

I have opened the short cut rope, used the zip line and slid down the slide from the ruins. Does anyone have any idea what I’m missing?