Debian 10 + Dynadock U3.0 - displays disconnected / not detected(?)

[CmdrBugbear]

Hi,
After enabling X / disabling Wayland, I've been able to get the displaylink-debian.sh (install) script to execute successfully.

I rebooted after installation and displaylink-debian.sh --debug (see attached file) indicates that it is installed and running:
---------------- DisplayLink info ----------------

Driver version: 1.6.0+dfsg
1.7.0
DisplayLink service status: up and running
EVDI service version: 1.6.0

xrandr --listproviders outputs the following (I presume this means my monitors are being detected. What does a working instance look like?):

xrandr --listproviders
Providers: number : 6
Provider 0: id: 0xfc cap: 0xf, Source Output, Sink Output, Source Offload, Sink Offload crtcs: 2 outputs: 8 associated providers: 2 name:modesetting
Provider 1: id: 0xd2 cap: 0x2, Sink Output crtcs: 1 outputs: 1 associated providers: 1 name:modesetting
Provider 2: id: 0xb0 cap: 0x2, Sink Output crtcs: 1 outputs: 1 associated providers: 1 name:modesetting
Provider 3: id: 0x8e cap: 0x2, Sink Output crtcs: 1 outputs: 1 associated providers: 0 name:modesetting
Provider 4: id: 0x6c cap: 0x2, Sink Output crtcs: 1 outputs: 1 associated providers: 0 name:modesetting
Provider 5: id: 0x4a cap: 0xf, Source Output, Sink Output, Source Offload, Sink Offload crtcs: 6 outputs: 5 associated providers: 0 name:ATI FirePro (FireGL) Graphics Adapter @ pci:0000:01:00.0

I ran the xrandr --setprovideroutputsource commands. These commands didn't have any apparent effect. Are the parameters for this command dependant on the providers listed above? If so, which should I have chosen?

When I run xrandr without parameters I get the following (my laptop lid is closed and I'm running of a screen connected via a single HDMI-out port, and my dock has two monitors connected, one via an HDMI port, and one via a DVI port):
xrandr
Screen 0: minimum 320 x 200, current 1920 x 1080, maximum 8192 x 8192
LVDS-1 connected (normal left inverted right x axis y axis)
1920x1080 60.01 + 60.01 59.97 59.96 59.93 40.01
1680x1050 59.95 59.88
1600x1024 60.17
1400x1050 59.98
1600x900 59.99 59.94 59.95 59.82
1280x1024 60.02
1440x900 59.89
1400x900 59.96 59.88
1280x960 60.00
1440x810 60.00 59.97
1368x768 59.88 59.85
1360x768 59.80 59.96
1280x800 59.99 59.97 59.81 59.91
1152x864 60.00
1280x720 60.00 59.99 59.86 59.74
1024x768 60.04 60.00
960x720 60.00
928x696 60.05
896x672 60.01
1024x576 59.95 59.96 59.90 59.82
960x600 59.93 60.00
960x540 59.96 59.99 59.63 59.82
800x600 60.00 60.32 56.25
840x525 60.01 59.88
864x486 59.92 59.57
800x512 60.17
700x525 59.98
800x450 59.95 59.82
640x512 60.02
720x450 59.89
700x450 59.96 59.88
640x480 60.00 59.94
720x405 59.51 58.99
684x384 59.88 59.85
680x384 59.80 59.96
640x400 59.88 59.98
576x432 60.06
640x360 59.86 59.83 59.84 59.32
512x384 60.00
512x288 60.00 59.92
480x270 59.63 59.82
400x300 60.32 56.34
432x243 59.92 59.57
320x240 60.05
360x202 59.51 59.13
320x180 59.84 59.32
VGA-1 disconnected (normal left inverted right x axis y axis)
HDMI-1 connected primary 1920x1080+0+0 (normal left inverted right x axis y axis) 819mm x 460mm
1920x1080 60.00*+ 50.00 59.94
1920x1080i 60.00 50.00 59.94
1280x1024 75.02 60.02
1280x960 60.00
1360x768 60.02
1152x864 75.00
1280x720 60.00 50.00 59.94
1024x768 75.03 70.07 60.00
800x600 72.19 75.00 60.32 56.25
720x576 50.00
720x576i 50.00
720x480 60.00 59.94
720x480i 60.00 59.94
640x480 75.00 72.81 60.00 59.94
720x400 70.08
DP-1 disconnected (normal left inverted right x axis y axis)
HDMI-2 disconnected (normal left inverted right x axis y axis)
HDMI-3 disconnected (normal left inverted right x axis y axis)
DP-2 disconnected (normal left inverted right x axis y axis)
DP-3 disconnected (normal left inverted right x axis y axis)
DVI-I-5-4 disconnected (normal left inverted right x axis y axis)
DVI-I-4-3 disconnected (normal left inverted right x axis y axis)

I have a couple of questions at this point:

• Is there a way to know whether my dock is actually supported?
• How do I get the screens connected to the dock to be shown as connected?

debug_20201004.txt

Hardware configuration info:
(Not sure if this info is relevant but I'll provide it regardless)
Laptop is a 2012 Alienware M17x R3
VGA port has nothing connected
Mini-DP port has nothing connected
HDMI port is connected to a screen
USB3.0 port connected to Toshiba Dynadock U3.0
Dynadoc has HDMI and DVI ports, both connected to screens.

I've also attached the output of dmesg when plugging in the Dynadock.

dmesg_20201004.txt

[kngharv]

try this:
#469

[CmdrBugbear]

OMG you're an f***ing legend (forgive the profanity).

I ran the command: xrandr --setprovideroutputsource n 0 (n times, where n is the number of providers).

Initially nothing happened, but then I realised the dock wasn't plugged in. Pretty much straight away all my monitors woke up. I'm excited because up until now I could only get this laptop to output display on up to two screens, no matter how many video out ports were pluged in. Didn't know how to make it output to any more than that.

Thank you so much.

I'll drop a tip in the jar today.