Parking this here. Haven't found much of substance, but for what it's worth, I found a Google Groups reproduction of a Guardian obit covering the services of choreographer Irving Davies (who I just discovered not only has a page on here, but also has a legit TMS connection! Ya learn something new every day...).
Anyway, among those listed as attending Davies' services is a "Mr Jess Whitfield." I guess this may help clear up the long-ago decade-old confusion on Whitfield's gender, provided it's the same one who worked with Miss Uggams over twenty years before. Regardless, just thought this would be of interest.