Cable questions. Multiport to 2.5 to LDR (resinlapse)

[RJacket]

Hello everyone.

So I have really wanted to grab a timelapse of my resin printer. 

Uncle Jessy from youtube has come out with a pretty cool cable that is a photoresistor that can take your shots as the leds are firing inside your printer.

Resinlapse Cable
Resulting in perfectly timed prints as it raises out of the vat.

My question though. The cable he made is for Canon cameras.
So I purchased an adapter that should work in theory. See below.

Lanc cable

But I got it all together today and it does not work. Unless I am missing something.
Is there a setting I need to turn on to get the Multipass port to look at what is plugged in?
I don't even know how to troubleshoot which cable is the one that is not working ,as I do not have a Canon camera on hand.

Did I do something/get the wrong gear?

Camera: Sony a6400
Lens: Sony SEL90M28G

Edited August 3, 2021 by RJacket