@ChuckPa
Ok, I also like to help with the implementation and supply all the information I get.
First, here is an example so that we can define what we are talking about.
4K Dolby Vision Dual Layer MP4 with EAC3
https://drive.google.com/file/d/1W3D6JFq5wL1c063Bnb9_KcEjMY-fkQHF/view?usp=drive_open
Media Info of the video track:
Video #1
ID : 1
Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main 10@L5.1@High
HDR format : SMPTE ST 2086, HDR10 compatible
Codec ID : hev1
Codec ID/Info : High Efficiency Video Coding
Duration : 10 s 719 ms
Bit rate : 696 kb/s
Width : 3 840 pixels
Height : 2 160 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0 (Type 2)
Bit depth : 10 bits
Bits/(Pixel*Frame) : 0.003
Stream size : 910 KiB (23%)
Encoded date : UTC 2020-01-25 12:03:28
Tagged date : UTC 2020-01-25 12:03:28
Color range : Limited
Color primaries : BT.2020
Transfer characteristics : PQ
Matrix coefficients : BT.2020 non-constant
Mastering display color primaries : Display P3
Mastering display luminance : min: 0.0050 cd/m2, max: 4000 cd/m2
Maximum Content Light Level : 1000 cd/m2
Maximum Frame-Average Light Level : 471 cd/m2
Codec configuration box : hvcC
Video #2
ID : 2
Format : HEVC
Format/Info : High Efficiency Video Coding
Format profile : Main 10@L5.1@High
HDR format : Dolby Vision, Version 1.0, dvhe.07.06, EL+RPU / SMPTE ST 2086, HDR10 compatible
Codec ID : dvhe
Codec ID/Info : High Efficiency Video Coding with Dolby Vision
Duration : 10 s 719 ms
Bit rate : 324 kb/s
Width : 1 920 pixels
Height : 1 080 pixels
Display aspect ratio : 16:9
Frame rate mode : Constant
Frame rate : 23.976 (24000/1001) FPS
Color space : YUV
Chroma subsampling : 4:2:0 (Type 2)
Bit depth : 10 bits
Bits/(Pixel*Frame) : 0.007
Stream size : 424 KiB (11%)
Encoded date : UTC 2020-01-25 12:03:28
Tagged date : UTC 2020-01-25 12:03:28
Color range : Limited
Color primaries : BT.2020
Transfer characteristics : PQ
Matrix coefficients : BT.2020 non-constant
Mastering display color primaries : Display P3
Mastering display luminance : min: 0.0050 cd/m2, max: 4000 cd/m2
Codec configuration box : hvcC+dvcC
We’re talking about the second video track that contains the Dolby Vision bitstream:
HDR format : Dolby Vision, Version 1.0, dvhe.07.06, EL+RPU / SMPTE ST 2086, HDR10 compatible
Definition according to Dolby (Page 14):
I am not a programmer so unfortunately I can not help to integrate this into the Exoplayer / Shield. But I can provide all possible DV examples and sound tracks.
Why should Plex do that? Why would that be useful?
As we already mentioned, you are currently dependent on a single fee-based program. Not everyone wants to buy DVDFab. More people could enjoy DV on the Shield or with Plex. The compatibility on other devices that cannot play DV is given because it is backwards compatible. It would currently be a unique selling point. The feature could also be reserved for Plex Pass owners (to possibly get the costs in through new members 
). In addition, the competitors does not sleep (emby)… If the exoplayer and the shield can do it, it should be added and intigirated. That would add another great feature to Plex 
The Plex Community will thank you!
KCX
