As you try to use different Remote with this box, the Power Code needs to be changed.
For Powerdown, this is done in your .toml file, and already works.
But when in Standby, Powerup is controlled by Bootloader (BL3), and this currently still listens to the old Power Code of original Remote.
That is the exact usecase for BL-Inject: CoreELEC BL301 Wake-Up feature [inject_bl301]
Maybe it works for you. But you should only try if you have a recovery image for your box, otherwise it may brick.
Also check the Remote Wiki procedure
As alternative:
The original ABX-12 Remote seems to be quite common, the same as used for Vontar X96mini or M96X II mini or X96 (mini), so you may check the *bay for replacement
