Kindle DXG update failed

Hi all

I bought used Kindle DXG with 2.5.5 firmware
Tried to update to 2.5.8 but update is failed.
There are launchpad, FBReader on it so I think
that there is some jailbreak that prevents successful update
I've tried many uninstallers I could find: update_jailbreak_0.4_dxg_uninstall.bin, update_jailbreak_0.6.N_dxg_uninstall.bin, update_jailbreak_0.10.N_dxg_uninstall.bin
Reset to Factory Defaults.
All in vain. error U007

I have the same Kindle DXG with 2.5.8 firmaware

Is there any way to update first Kindle using firmware from the second one?

I will appreciate any help