So if it is the same as 22 and 23 it might need benzyl alcohol in the colour developer. Try to see what sort of colour saturation you get before going that route from standard RA-4.
I have notes somewhere from when I was trialing some old ep/2 type colour paper ( See , this is a theme. I make notes, but locating them later... I tend to paste test prints into a spiral bound notebook, and write the filtration and processing steps on them if the steps were other than 'standard').
Development times for the colour develoepr were longer ewith EP/2 process as well. All of my old EP/2 paper that was gifted to me now has a marked yellow cast, so I have not pursued this experimentation any further.
As to reversal first developer: I was wrong on the thiocyanate. That must have been when I was goofing in making DIY slides with tmax 100 and pan F film stocks.
This reverasl before RA-4 b&w first developer (likely from Ron Mowray, but my notes are not explicit on the source) goes as follows:
per litre:
water , deionized or destilled about 750mL , microwaved to about 52C
pinch of sodium silfite from a 45g quantity
3 g of metol, stir (sometimes for a while, until all is dissolved)
balance of the 45g of sodium sulfite (stir til dissolved)
6g of hydroquinone (needles dissove quickly)
160g sodium carbonate, monohydrate ( takes a good bit of stirring to dissolve, may need more that 160g if your carbonate is not monohydrate)
sodium chloride 125mL of 2% solution ( ie disslove 2g NaCl into iL distilled, and then store the rest or toss after drawing off 125mL)
water to 1L
Let stand a minimum of 2 days to allow the hydroquinone to morph into it's sulfonate form.
use at 2' 20C 1:3 dilution as first developer for papers like Supra III
My processing sequence is :
2' FD total darkness, mostly constant agitation (what else is there to do unless you are doing this in a daylight tube?)
15" stop bath, b&w paper strength, with indicator, still in the dark if in trays
45" running water into tray wash. Turn lights on in this stage; it is necessary for the optical re-exposure. There are chemical reversal agents, bu not for my use when sloshing prints in trays, thank you.
Then conventional RA-4 processing.
Adjust density by varying exposure time or aperture. If correcting colour cast by changing filtration, the exposure adjustment are even more important that when printing conventional RA-4.
Good luck with your experimentation.