Oh I'm so sorry to hear she's unwell again! That's the thing with the DAMN teeth, it's one sickness after another until they're eventually out. You were doing SO GREAT! i think you should handle it just like you did it last time, sp. since it's so fresh, she'll remember it. WIth the proper pain medications and being careful of her not having a stuffy nose when going down, she should be back to sleeping nice in a short while. I know how much you've struggled but remember each sleep training process has its setbacks, let alone when undesired sicknesses make their appearance.
As for the 2 naps, i'd recommend first to lenghten her nap if it's too short. It's probably due to the cold since noone can sleep well with a stuffy nose. Make sure her nose is clear when going down, put a humidifier in her room, maybe rub some Vicks on her chest and back before going down and try that nap to be a long one (i have sometimes used my good friend Benadryl to get a good nap when ds has a cold, ask your ped). If you still can't succeed in getting a long nap, then try for a catnap on the early afternoon, maybe in the car o stroller so she won't get congested for lying down.
HUGS HUGS I know how hard it is. Let us know how you get on!