It’s really great, to read your post of commitment and devotion, that I happen to share, also it luckily was an easy mail-order case for me, so I can’t really say I would have had your persistence as well.
And I share your experience of reboots and battery problems as well.
For Motorola Mobility I found a reference in the wikipedia posting on “Foxconn”, that they are their customers (i.e. Motorola customer of Foxconn).
Source of this information is an older (2012) article in the Huffington Post “Foxconn by the Numbers”.
As Motorola Mobility is a part of the Chinese Company Lenovo since 2014, I guess, they will now produce the phones in their own factories.
Well, you can say what you like on paper, so I have no clue, how much is there behind the “Lenovo sustainability reports”. Chapter 6.0 is focusing on manufacturing and supply chain operations. That at least sounds better thant what I heard about Foxconn.
Yet, I am sceptic (even though I am wrtiting that post on a Lenovo ThinkPad), and would like to believe in it.
The "Greenpeace Guide to Greener Electronics has Lenovo ranked in fifth place (of 17).
With regard to that report, see the following thread as well:
(Beware, the thread turns a bit off-topic in the end. 
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