That looks OK to me.
Debugging CEC when it is in the kernel is quite tricky, which is why we are going to work on libCEC. The very nature of CEC can also be buggy.
You can try sending a reset signal:
echo 0x0 > /sys/class/amhdmitx/amhdmitx0/cec_config
That seems to fix some TVs, like old Samsung sets and I am considering sending an extra reboot on bootup.
Is there an AVR between the projector? I’m assuming so. Can you wire it directly to the projector?
Sam