My progesterone is a 5.0 with beta 524 at 4/5 weeks pregnant. is there any chance of a viable pregnancy?

A viable pregnancy is still possible, since ovulation may be delayed, and fertilization likewise , making the HCG determination likely for early pregnancy. See your OB physician for a repeat of the HCG serum test in a few days or immediately if there is bleeding or pain, as low HCG could occur with poor implantation, as with pregnancy outside the uterus (ectopic).