So, update. I called HR yesterday afternoon and asked about company policy regarding employees being required to take PTO and LWOP. Both the HR rep and her supervisor stated that the company cannot do that, but that not doing so may be reflected in my evaluation.
This afternoon, I received a call from HR offering me a severance package (two weeks pay) in exchange for an agreement that basically prohibits me from suiing for lost salary and damages. I am inclined to accept this and go quietly.