Dosimetry/Radiation Therapy is a small profession and just like Nuc Med has a low turnover, too many schools, and very few openings each year. Honestly I don't think its worth the risk to spend more time and money on a "big maybe" for Dosimetry right now. Too bad cause Rad Therapy is a pretty good job, nice hrs/salary, little or no on-call, but again same as Nuc Med, few openings anually.,
PA offers a much better outlook, although be careful to check the entrance requirements (pre reqs) for PA, from what I know most of the programs are extremely difficult to enter. A Nuc Tech I worked with tried to get in a PA school, she said it was really tough.
Some laid-off Nuc Techs I know have gone back to school for Medical Lab Technology(ASCP)