Cosmote tvbox dtb?

I got a cosmote tvbox which made by skyworth digitals.the SOC is s905x4-bu ,in android support dolby vision.the motherboard vision is hy44g.
i got the ota.zip and unzip the payload.bin.and use extract-dtb tool to get a dtb file.but neither adb methord nor update.zip methord cannot work.the screen stay black till i disconnect the usb storage.
here is the ota.zip link

2a95458d9321873c8b2df36c73ac1473ec847763.zip
, thx in advance for any help.

You need to test if CoreELEC boots at all. Skyworth is known not support third party systems at all.

https://wiki.coreelec.org/coreelec:devgeneric