For $29/mo, we provide access to advanced level technicians who will answer your questions on any Macbook board related matter to the best of their knowledge promptly & walk you through how to solve your problem so you can deliver a working board to your customer.
R1442 can't cause lower reading; it is a pull-up resistor.
I suppose that you reffered to SSD_BOOT_CONN_L.
If R8642 is not used, U8640 is the suspect.
If U8640 is not in place, you should lift R8642 for test; not touching above mentioned components at all.