How recovery hacked RB2011 via JTAG ?

I knew that my router could be hacked and managed to update the firmware (current 6.42.7), but did not manage to update the password. Now I have a hacked router and seeing the problem, I ask for help in recovery.

As it became clear to me recovery using NetInstall is not possible. Having examined the router, I saw something similar to JTAG, is recovery possible through it?

i can’t re-hack … my firmware closed bug.

Factory reset and then restore backup then change the password?

Why can you not netinstall?