Hello and welcome to Just Answer.Sorry your friend is in this spot. No she cannot take Provera or Prometrium to induce a period. In fact progesterone is used to support and maintain a first trimester pregancy.She is eligible if she is only 2 weeks late for a medical termination of pregnancy which is done with medication only. This can be done up to 9 weeks of pregnancy at most centers.
Medical termination of pregnancy is done with a combination of medications and under a Drs supervision. It is 97% effective and is safe for most women.
You can self refer yourself for an NHS funded pregnancy termination using the below links.