Display black - Qiangli QPro 2.5 RPI4 128 x 64

I have an indoor QPro 2.5 from Qiangli but I cannot get any LEDs to so much as flicker on:

Specs here:

I am using a couple of lithium ion batteries and stepping down to the require 4.5V. When I run the spinning square demo I see the volts on the RGB lines fluctuate slightly. I also see the Amps drawn fluctuate on the power cable, but only between 0.16A and 0.25A. So it seems there is some response to the rotatation of the square as before I start the demo Amps drawn on the power line is constant and Volts on RGB is too.

I accidentally shorted a previous pair of batteries so I know they can deliver 18Amps in a short burst so I don’t think the problem is current related. It seems like none of the pixels are getting enabled and so not even trying to draw current.

I have disabled sound, tried all the multiplexing options and chipsets. I have pins connected in the following way:

|1|RD1|Red data signal
|2|GD1|Green data signal|
|3|BD1|Blue data signa
|4|GND|Power ground|
|5|RD2|Red data signal
|6|GD2|Green data signal|
|7|BD2|Blue data signal
|8|E|Row control signal|
|9|A|Row control signal
|10|B|Row control signal|
|11|C|Row control signal
|12|D|Row control signal|
|13|CLK|Clock signal
|14|LAT|Data locking signal|
|15|OE|Enable signal
|16|GND|Power ground|

Does anyone have experience with this or similar panels. Can anyone help?

Note I just want to get some LEDS to light. I don’t mind at the moment if they are in the wrong place. My guess would be if LAT, OE, CLK and at least one of RGB is working correctly I should see something.