For anyone arriving at this thread looking for answers regarding their non booting (no Nintendo logo at start) EZ-Flash Omega.
If replacing the crystal oscillator according to the "basic repair guide" (mentioned above) doesn't repair it then...
on this forum there are comments with attached dumps, if you are interested in them.
Here is link:
https://gbatemp.net/threads/ez-flash-omega-bricked.628593/
One of them is wrong size, or it should be related to different memory on the chip in...
I am sorry for that to happen.
From my experience, absence of bottom logo at boot is mostly not because of faulty crystal resonator, because they are rarely damages. And because your cartridge become bricked exactly after updating firmware, its...