after you take the mifepristone the embryo is no longer alive. you start your period maybe a couple hours after taking the pill. all the second bottle does is force it out. i would be weary of a drug that says it can reverse any kind of affect that the mifepristone had on the embryo.
taking progesterone orally doesn't make any sense -- progesterone is metabolized very strongly by the liver. all of the progesterone taken this way will be converted into metabolites within hours of ingestion. there is no way this pill is supported by the science.
basically, the first pill blocks the bodies production of progesterone, which is necessary for pregnancy. the reversal pill is attempting to restore progesterone in the body so pregnancy can continue but in a way that can't possibly work.