iPhone 8 Minimum Required IC's to Boot?

[crc2018]

Currently working on an iPhone 8 (intel) for data recovery with heavy water damage around the PMIC area - numerous resistors burned/loose which i've replaced and fixed the tracks underneath, several shorted caps on VDD_Main and VDD_Boost which have been removed. I've also removed the top speaker amp U5000 as there was heavy water damage around it. Board has also been cleaned. Phone turns on with backlight and image and then after a few seconds shuts off and reboots. Tried pulling the audio IC U4700 off as well (also had signs of corrosion around) - found some corrosion underneath it which i've cleaned up but not replaced the audio IC back onto the board - phone still reboots but it's taking longer to reach that point now.

Quick questions:
First will the 8 boot with no audio IC present like the 7?
Second will the 8 boot with no speaker amp present?

[crc2018]

As an update to this i've replaced the audio ic and top speaker amp but the behaviour didn't change.

Thinking maybe we might have software corruption given the sheer amount of liquid damage on this phone I decided to try a restore with data through 3utools - this process completed successfully the phone took the update no issue.

However the phone is still turning on making all the right signs and right before it should be bringing up the lock screen it just reboots. Clearly there is something somewhere which is not communicating properly but that is not required for the phone to perform a software update. Further visual inspections have revealed nothing. I may have to conclude this one not recoverable which is frustrating as it seems i've got it so close! There are also some faint vertical lines appearing on the white apple screen at two times during the boot process which disappear. Carefully looked around the 5.7V Meson line for issues as i've seen the vertical lines be caused by this line before but its totally clean - no liquid got near it.

The behavior is identical in a known good housing and also on DCPS with just the screen connected.