Xiaomi Mi4 in Recovery Mode loop & no connection with PC

Hi! I’d be extremely thankful to hear your thoughts on this case.

I’ve got a Xiaomi Mi4 in a recovery mode loop (Mi Recovery 2.0.1) that can’t enter Fastboot mode and can’t get connected to a PC to get flashed. There is no SD card slot for this model to upload a ROM (update.zip in this case) on or it would be a cake.

History:

- phone was dropped from the 5th floor. Everything works properly (getting calls, messages) except for the LCD touch and the VOL UP button.

- out of warranty so ordered a spare LCD. I have experience fixing 15+ different phones with the same issue successfully.

- while getting the battery out carefully following a YT video while disconnected from the circuit board and all the other components the battery pack started heating quickly and smoking. Most importantly, it was disconnected from everything when this happened. I was using plastic tools when removing it but it could still be caused by sloppiness.

- ordered a spare battery

- ordered a spare power/volume control unit (not received yet)

- got new LCD and installed it. When booted (both holding power button or vol(-) + power button or vol(+)+power button) the phone goes to Mi Recovery 2.0.1

- wiped all data using Mi Recovery but still can’t boot to MIUI or Fastboot

- phone is charging when the micro USB is plugged into a power source.

This gets us to the next logical step – flash a new ROM:

- got Mi PC Suite to flash but can’t connect

- got Mi Flash Tool but it can’t find a device

- got ADB/Fastboot but it doesn’t find a device with "all devices" in command line

- got the phone charged to 100% as advised by a YoutTube video but nothing changes.

Next logical step – find drivers and try different PCs. Those are the drivers I installed on 2 laptops with Win 7 Pro and Win 8, as there was no notification of a new device in Device Manager. I have always restarted PC with Disable Driver Signature Enforcement option:

- Minimal ADB Fastboot

- official Xiaomi Mi4 drivers for Windows

- Samsung Android drivers

- Qualcomm Hs Usb Qdloader 9008 Com3 Driver

- OEM USB Drivers

I have also tried:

- removing the ‘Disconnect power from USB ports while not in use’ feature in Device Manager

- Adding a device using Devices and printers (PC can’t find anything)

- having the device both turned off and in Recovery Mode while plugging to the PC.

Last hope: getting the volume/power button unit replaced so I can get to Fastboot while holding VolUp and Power, but that doesn’t help the case where it’s not recognized by the PC.

Thanks!

UPDATE 10 AUGUST

To anyone with the same issue: I've replaced the volume key and it worked. Took me to FASTBOOT mode (Bunny fixing logo). I still can't connect to the PC. But I got to MiRecovery and to Wipe All Data> Reboot > Reboot to System One. Now I'm at MIUI7 start screen.

Waiting on new LCD so I can setup the phone and update the thread.