This isn’t directly my field (I’m in a related one) but I don’t think a master’s program would help. You can ask the admissions departments of these schools directly - but to my knowledge, the programs are really laser-focused on your prerequisites because they are so crucial to the classes you will take in a master’s program. You need to have a strong grasp of organic chemistry to succeed in medical studies; that’s why med school makes you take it, too!
Also, as a comment on the direct patient care requirement…the role of a physicians assistant was designed as an advanced medical care professional whose experience and expertise in patient care allows them to perform more advanced care, such as diagnosing and treating illness. Similarly, nurse practitioners are meant to be advanced nursing roles. It’s in the (full) name - “advanced registered nurse practitioner.” The role was explicitly designed for people who had more assistive/paraprofessional roles in medicine and wanted to take a step forward in the kind of care they provided. Thus, the training and education builds on that patient care knowledge. The idea of students wanted to go straight from college into PA school is very very new - I’d say 10 years ago most people didn’t even know what a PA was.
Put bluntly, you need more patient care experience, especially because you failed o-chem once. You may find it very difficult to get into PA school even if you do get more patient care hours - these programs are very competitive these days - but that would be your best shot, IMO, unless you find some way around the school only taking your first attempt at the course. As nothing can guarantee your admission, if you’re not motivated to do these jobs to have a shot, then I think perhaps you should explore alternate careers.
Paramedic is a separate career track in and of itself. Paramedic requires 2 full years of specialized training, plus passing a rigorous national licensing exam. Paramedics can be accepted into PA school (the PA degree was originally designed for paramedics who wanted to expand their scope of practice), but one doesn’t need to be paramedic to demonstrate interest in emergency medicine for PA program. AEMT (Advanced Emergency Technician) also gets plenty of hands on, has a higher level of responsibility and a broader scope of practice than an EMT, who are often relegated to just driving the ambulance. AEMT requires less formal training than an EMT-P (paramedic)
Medical scribing is largely a clerical position and does not offer much, if any, hands-on patient interaction and isn’t recommended for PA school hopefuls.
The CASPA definition of PCE [patient care experience] is “experiences in which you are directly responsible for a patient’s care” rather than HCE - “both paid and unpaid work in the health or a health-related field where you are not directly responsible for a patient’s care but may still have patient interaction.”
PA schools want applicants to have PCE–and the number of minimum hours vary by program. Some do require into the thousands of hours, but many others only require several hundred (I’ve seen as little as 300 for some programs).
A grad degree isn’t going to remediate your undergrad GPA since grad and undergrad GPAs are calculated separately by CASPA and only the undergrad GPA is used by PA programs to make interview and admission decisions.