From what I've gathered in the meantime I take it they cannot simply open withdrawals due to regulation for the fact they're probably required to know who they're dealing with. But this doesn't excuse them giving the impression we'd be able to access funds, of course.

I would recommend never using Poloniex, and even more so now.
The past couple of months they have had numerous withdraw and deposit issues that were never resolved.  Now they have also locked numerous accounts with coins that could not be removed or held in limbo.
After months of waiting on tickets and being promised it would be worked on, it never was, so I have simply counted all my coins on my account as a loss.
Not like they were worth as much as when I first tried to withdraw them...