I think your analysis is pretty much spot-on, but I would ask you as a lawyer to answer this hypothetical:
If hiQ had scrupulously and categorically avoided ever using logged-in accounts (as opposed to the facts claimed re 'Turkers') would LinkedIn still have had the leverage to shut us down?
Also note that LinkedIn, as part of its strategy to force us to settle, threatened to permanently delete the _personal_ LI accounts of everyone who worked at hiQ. How does that sit with you ethically, knowing that a LinkedIn account is precisely what you must have in this business, especially when your company shuts down and you need to seek employment?