System Information
Retest Compatibility Report
The problem remains with videos being skipped with Proton 5.0-7.
With unofficial/custom Proton 5.8-GE-1 (https://github.com/GloriousEggroll/proton-ge-custom/releases/tag/5.8-GE-1-MF) the game is playable now with working cut-scenes :+1: (the only remaining issue that the game pauses at the end of some cut-scenes until you press mouse button).
steam-633360-5.8-GE-1-MF-4-gbefbdfc.log.zip
steam-633360-proton-5.0-7.log
system_info.txt
The intro videos are working now, but appears to have wrong brightness/colorspace
How it should look:

How it looks playing through Proton:

including the mediainfo of that particular video
media_info.txt
steam-633360.log
system_info.txt
The same problem occurs also with recent GE protons versions
proton 5.0-7x1 2020-05proton 5.8x1 2020-05
Compatibility Report
System Information
Distro: Linux Mint 19.1 Tessa (64 bit)
GPU: Vega 56
Driver/LLVM version: Mesa 19.1.0-devel/9.0.0
Kernel version: 5.0.7-050007-generic
Proton version: 4.2-3
I confirm:
Symptoms
Game works fine except that all of the cut-scenes are skipped.
I spotted some mfplat stuff in the logs, also included mediainfo of one of the cut-scene videos.
media_info.txt
steam-633360.log
system_info.txt
Reproduction
Just launch and start the game, jumps straight into gameplay.