Option 1 is T-Mobile acquires Shentel. As I understand it, T-Mobile would have to pay a price equal to the value of the entire company, but I'm not clear if that would mean paying an inflated price for just the wireless part of Shentel or if it means they have to buy Shentel outright. In either case, it would seem to be aimed at making a buy-out unattractive, or at least, that's how I read it.
Option 2 is Shentel can acquire T-Mobile's customers and network in its region at a discount. If Shentel needs financing to fund it, I believe T-Mobile is obligated to provide it, or at least arrange for it, at a low rate.
Option 3 is neither side decides to spend any money. In that case, T-Mobile shuts down operations within the Shentel region within two years.
My preference is definitely for Option 2, though I'd accept Option 3 as well. My assumption is that Option 2 would lead to a more orderly merging of the networks than Option 3 would, and would imply some level of working together. It would also allow for Shentel to receive the income from T-Mobile's current customers in the region, however many of those there might be.