Did you ever find this ? Im in the same situation

No I did not. Ended up using the tinyleds sled. If you do go that rought... make sure you bridge either the 5v or batt pwr option on the back of the sled or you will get not pwr to the vtx. Thought my vtx was dead but turns out user error. Sucks that they do not post instructions for us new to the hobby or like me who has been around a little bit but do not have access to racing clubs. Nearest one is 2hrs and hobby shops charge alot to work on quads.

I've got the tbs toothpick mounting board too and just soldered the Rx and Vtx yesterday. I used a multimeter with a continuity-function (beep-mode) to see what's what. There seem to be different versions of this board, but these were my findings:

a) I've got two pads marked as 'cam', one on both sides. This confused me at first, but they are not connected to the RX nor VTX at all. It seems to me they are just a plain pass-through for easier wiring. You could use them but you may also connect to camera directly to the flightcontroller and ignore these pads.
b) I've got a pad marked as 'vtx' and it's used for video-signal input. I know because there is 75ohm impedance between the VTX and ground. I will wire the camera to the flight controller for OSD and then from the flight controller to the VTX pad on the toothpick board.
c) The 5v-input and 5v-output pads are not simply passthrough connections; the Unify VTX does some sort of filtering (Warning! while the Unify Pro32 Nano accepts voltages up to 13v, the CRSF Nano receiver DOES NOT)
d) If all pads are soldered, then you get a TBS-specific connection between the VTX and the RX so they can communicate without flightcontroller. You can change VTX settings with LUA scripts. It works like a charm and that's nice, because this saves one UART connection and most 26x26 flight controllers are low on exposed UARTS (not that you need many on a toothpick).
e) If you want Smart Audio, there is a small pad on the front of the mounting board. And another one marked 'tx'. Easy to overlook. I'm unsure if these are regular pads or if they need to be bridged. I don't use Smart Audio. But in a normal situation, Smart Audio goes to a TX pad on the FC.

I created this. Hardly a wiring diagram, but hope it helps.

Great  thank you! I too had to do some deep digging to figure this board out. I can confirm your findings. Mine had the same layout and function.

I only have one more question ! Can you explain what you mean by (if tou solder all pads they can communicate) what pads? the two big long ones near button near bottom of your picture ? I have mine totally working now on uarts including smart audio without doing that, but i am curious. Thanks much !

You're welcome! And thank you for validating the findings :). It's a neat little board.
Regarding your question; I'm referring to page 8 of this manual: https://www.team-blacksheep.com/tbs-unify-pro32-manual.pdf.

It says that the Unify PRO32 has a full serial interface which has extended functionality compared to Smartaudio. This interface needs two connections:
Crossfire Nano pad named channel #3 ← Unify PRO32 (CRSF TX = big long one marked as 'B')
Crossfire Nano pad named channel #4 → Unify PRO32 (CRSF RX = regular smart audio signal wire)

If all solder pads are connected to the mounting board, the connection between Unify and CSRF Nano works out of the box. I'm not sure what the 'extended functionality compared to SmartAudio' exactly entails, but I use it for switching channel, band and powerlevel on the Unify without any flight controller connected. To do this, you can use the Crossfire LUA script on the controller. It will automatically show 'Unify Pro32 Nano' in the tbs-devices menu after binding/updating.

Thats awesome . I have the normal lua working so far, but I may try this additional functionality on my next build. TBS cloud is sounding like the glue that is going to tie all this functionality together. It will have the ability if you use the TBS fusion fatshark module, to automatically change vtx/module channels in sync via wifi, among other things. Not sure what the current state of affairs is with regards to functionality, but heres one basic setup walk thru.
https://madmikefpv.com/article/configuring-tbs-cloud

Thank you!

I have no jello, really happy with the result (make sure you tighten the zip ties good)

not sure about crash resistance, we will see, or hopefully not ;)

some sort of weatherproofing would be a good idea. clear nail polish works for me, a lot cheaper than conformal coating. I'll be getting a twig xl in a few weeks, may end up doing something similar as this looks badass.

thank you! I'm really happy how it turned out.