VLC 3.0.x e-AC3 Dolby Digital Plus coming out as bitstream on UpTab HDMI Adapter

[vlestat]

So I don't bury the lead, my question is: Does VLC on Mac take a Dolby Digital Plus (DD+) stream and convert it to a multi-channel (5.1) bitstream output through HDMI?

I have spent some time looking into this and still don't understand the truth since VLC troubleshooting is often tied to Windows.

I am trying to play back an (many) MKV file(s) with E-AC3 codec for audio (Dolby Digital Plus). They only send to my receiver as Linear PCM, though regular Dolby and DTS are sent correctly encoded to the receiver to decode. It gets weirder, but first, hardware I have been using:

I am using an UpTab Display port to HDMI 2.0 adapter compatible with HDR (I realize now that my Mac won't do HDR, oops). Uptab: https://www.amazon.com/gp/product/B01B702YTG/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
If this is the wrong adapter to best get 4k@60Hz along with Dolby Digital Plus, just link me to the right one and I will be forever grateful. If there is one that works particularly well outputting DD+ that is not 4k, that would also be fine if I can't get this working.
I also tried using the built-in HDMI port on my early 2015 Macbook Pro with no success in the DD+ department.
Both HDMI ports were set up correctly using the Apple Midi Output speaker utility thing for 5.1 audio

During my testing I tried to use some sample material to see what I was getting out of my speakers. I am able to playback the files with the receiver doing DD+ decoding if I network stream the file to my TV's network player so I could compare the sound coming out to VLC on Mac.

I want to know if I'm losing my mind, but it seems like the bitstream coming out is multi-channel. Any devs that can comment?

If I'm not losing my mind, then you devs are magical wizards to be able to do that kind of conversion on the fly.