Okay, so I've decided to forgo the second core set and just printed out proxies of the cards that are missing 2nd and/or 3rd copies.
Went to GenCon with a friend and played in the Massing at Osgiliath preview event with two other players. We had two hours to attempt it as many times as we wanted, but by the end of
our time slot, we had only just managed to make it to the 2nd of 4 quest stages! VERY difficult scenario.
Unfortunately for me, my friend and I didn't arrive in Indy until 5:50pm local time and the dealer/exhibitor hall closed at 6pm, so I jumped out the car and ran to the FFG booth while my friend drove around the convention center until I had successfully found us each a copy of the new adventure pack Conflict at the Carrock. Well, it was not to be, as they brought a very limited supply and sold out on Thursday! Even worse, none of the other dealers brought any because they were under the impression (true or not, I never found out) that FFG had exercised their exclusivity right, so we were out of luck there too! Anyway, my friend ended up buying a copy off of one of the guys we played with for the Massing at Osgiliath event ($20 instead of the $14.99 + tax at the booth, so not too bad considering), and I purchased a copy from my local gaming store when I got back into town.
Long story, but it was a lot of fun, and I'm looking forward to more adventure packs.