I think it's already been pointed out who "Donald" actually is.
Florence Delarosa (aged down to teenager)
Melissa & Chris Roomies (though I was lazy and just cast two Downtownies in their roles: the sparkly dress lady and the cowgirl)
And finally (in the back):
Tina and Gina
They are the result of a breeding experiment between two characters who don't canonically have kids, just to see what their hypothetical kids would look like. You can probably guess their parentage.
I threw them in there because I'm playing with a clean hood and needed some extras, though it now gives the chapter a strange back-to-the-future feel, having them present when their parents first met.
Also, the llama is actually Mortimer doing double-duty, since I had him on the lot, and the streaker is Kvornan Tricou (picked at random).