You understood me correctly; pity the prev. post vanished but I guess I was too carried away commenting the lovely article :o)
It doesn't look very probable the crew made note of the ravine in their previous approaches as it is not steep and, presumably, didn't cause them any troubles in previous flights. Why would theuu spot the slope , from air, at all? Or may be they meant approach from the other side, where there is also a ravine, but with a steeper slope? We don't know from what side the Polish planes approached the runway in the previous years.
I'd say by the hole they meant the airport with an absence of ILS. But can be of course, someone of them had an attentive eye and remembered the landscape, like, in general, that the aerodrome is on an elevated piece of land - glance at it from any side.