Rudeofus is correct, in that either potassium bromide or benzotriazole will work, but test with SMALL quantities, as this stuff really stops RA-4 developer in its tracks! Add a tiny, but measured, amount to 100ml of developer working solution and see what happens before wasting a whole liter of developer.
Addionally, try this: Expose the paper for twice the time (maybe even longer) and develop diluting your color developer (with the bromide or BZ added). Essentially, developing for an effectively shorter time (dilution) will hold back that fog and the extra exposure will add the needed density. This is not a perfect solution but is one worth evaluating with practice,
I use NO safelight for either B&W or color printing. I do not OWN one! Reason: I trust no light. - David Lyga