I have to report her to the OSPCA...?

Your situation really sucks - I'm sorry. It sounds like she may have good intentions and want to help animals, but doesn't understand what they need and doesn't have the resources to take care of them. Those dogs really do need to see a vet. I think you are right to call the OSPCA. I think you can tell her or not, whatever you feel is best. I'm sure she'll be upset, but it's not OK to allow that many animals to keep hurting. Thanks for your caring and noticing! So many people just look on and do nothing.