(((Hugs))) from me as well. My 27 month old Katie has also had her ups and downs, but it certainly could be the molars causing the probelm - we have had teething on and off for the 2nd year molars for about 6 months now.
We have never had a 3am start to the day, but the last two days have been 4 am 'starts', most definitely down to a cold / cough that Katie has.
We have a NW of some sort most nights - I go to Katie's bed (a double mattress on the floor - lol!) in my sleep to deal with this, so don't normally even remember going through. I made the decision to stick with this arrangement until it runs its course, even if that is until Katie is 5 or 6 yrs old or older (we are not planning on a second child). Anyway, this is of no help to you, just some background.
What I do with a 4am 'start' (NOT recommended BW way, I am almost certain!) is go downstairs with Katie, leave the lights off, put Baby TV on (channel in the UK which has lights and music most of the night) on REALLY low volume, give Katie pain meds and warm milk, put the sofa cushions on the floor with some pillows and a blanket and encourage Katie to lie down with me so we can drift back to sleep, even if it takes till 6am and we have to get up at 7.30am.
As I said, NOT recommended technique by anyone's standards, but this has been a blessing for us on many occasions and has not (and I really don't know why) become a prop or a routine - it's just a saving grace for us - a way to get a little more sleep during the rough and tough times.
What I think might be more recommended is going back to doing some kind of gradual withdrawal - i.e. staying with her at bed-time and NWs and early wake ups until she is able to drift off with you there, holding her, then slowly moving towards not holding her, then slowly moving towards the door until you are out of the door.
If she is experiencing separation anxiety, then walk in / walk out may be just too hard on both of you (another technique which does work without totally abandoning your child).
I think you need to decide what might work for you and run with it for a week or so - it may be that you just have to ride through it for a few more weeks and do whatever it takes to maximise the amount of sleep you ALL get.
I constantly worry about Katie not getting enough sleep and her suffering as a result now and in years to come. It's very hard not to.
Really hope this period passes quickly for you (and it WILL pass - I promise!!).
xx
PS Top tip from 'No Cry Sleep Solution' by Liz Pantley and also from ROCRO (Raising Our Children, Raising Ourselves) that I have just started to see some brilliant results from for bed-time, is telling made up stories in the dark after 'lights out'. I have been going back over long 'forgotten' fairy tales from my youth (and have really enjoyed it!) - you know, 3 Little Pigs, Snow White etc etc - Katie drifts off within MINUTES and I find myself finishing the story and not realising she has fallen asleep - a good way to keep her and me calm - might be worth a shot.