I don't think that's a walkthrough problem. It's just how the game is.so following the walkthrough you won't be able to get all the scenes can you? Like walkthrough forces you to be the only friend with Niki (kiss option )and also heather last scenes will be automatically be blocked.
Is it possible to get all the scenes or not?
I am at mermaid quest and just figure out there is a scene list option
And after the gobline mountain quest, you won't be able to learn Stealth? I don't know but my alignment is dipped towards the honour and I opened the letter also did the Selena scenes and I don't remember doing anything honourable except saving the Trevor.
You can't get everything in one playthrough.
Check the scene guide in game and you'll see some of those need you to pick a different choice to another scene