Hello and Welcome to the forum,
We already have a thread for AMlogic TV Boxes.
Some of the list of devices with their dtb here
For more information you can also follow in this thread
If any other user have tried it on Tanix TX5 Plus then they will be able to advice.
As per CoreElec DTB it is a S905X3 soc which is SM1 you should try sm1 uboot and test all sm1 dtb one by one.
Good Luck.