Unfortuately, those formulas assume active gelatin to do the chemical sensitization step and therefore your speed and contrast are too low to be practical.

For that emulsion, try heating with 50 - 100 mg of sodium hypo pentahydrate / mole of silver added as a 1% or 0.1% solution in distilled water. The addition should be at 60 degrees C and the emulsion should be held for about 1 hour.

Unfortunately, I cannot predict the exact amount or time for you as this must be done by trial and error or you get fog. So, I advise you to try it on a small portion of the emulsion first. I methods for doing this elsewhere.

Proper finish should increase speed by 2 - 3 stops, and contrast by 1 or 2 grades. My emulsion for enlarging paper is typically the same as for Ilford MGIV paper wiht the grade 2 filtration. But, I use an entirely different prep.

BTW, the excess bromide will retard the action of the hypo sensitization, another reason that I can't give you a prediction for what will happen.