First off, thanks & praises to all the lovely people who volunteer their time and help out so many of us.. what would I do without you & this board?

Today I have a few more questions..
I am an Austrian citizen in the UK, I have been working for about 4 months (got my registration certificate!!) and my girlfriend had been staying with me in London on a tourist visa. She is a Venezuelan citizen with a US green card (permanent residence).
We've been together for 5 1/5 years, living together the whole time but unfortunately nothing was in both our names, so we cannot go the EEA family permit route and have to shell out the 500 quid for VAF4 for settlement based on proposed civil partnership (which we were going to register ASAP anyways) - anyways.. she left today to go back to America

Now she's waiting to apply at the New York office (unfortunately they don't accept in person applications anymore so she is going to have to send it all in after completing the online application)
We had been living on my wages & also our combined (cash) savings.. now that I have to officially sponsor her I have to get another job, because my wages are rather low (890 net pay / month) and our rent is rather high (650 not including anything), anyways.. to make a long story short.. our savings are gone, except for 1000 pounds that my mum (from Austria) just deposited into my account a few days ago to cover rent & bills after having to pay the 500 pound visa application fee and the flight to New York.
The good news is that I found another job which will bring in an additional 880 net pay per month, so that would be more than sufficient according to our budget, but I haven't even started working there yet!!
I start work on Friday and I am not sure when I will receive my first payslip.. my proposed civil partner's father is going to write a letter saying that he WOULD support us if it came down to it and he will include bank statements to prove that he would be able to do so.. he lives in the US and has a high paid job at the University of Maryland.
My mother already gave what she could afford, which was the 1000 pounds (early christmas & birthday present)
I read that third party support is permissible if the third party is in the UK.. is that true? Would they not consider my girlfriend's fathers declaration just because he's living in the US!? and what about my mother's deposit, it's already in my account so I suppose that would be okay...
and my 2nd question is, I have payslips for 4 months from my first job and none (maybe one by the time she will apply) from the second job.. would that be enough? we would include a budget showing that 1770 a month is more than enough to support our household and hopefully a letter from my second job saying that I work there and make so and so much.
What do you think?
Already my girlfriend has to postpone her flight, because we thought that you could just walk in and present your case at the British Consulate General in NYC - reality check, you have to send everything in, then they will let you know within 5-14 business days and then they have to send it back (at least they use overnight express mail for that)
So this already delays her application by at least a week or so.. and we really don't want to wait too long, but I am worried that the ECO will frown upon my incompetence

I keep telling myself I have to stay positive, but unfortunately I am not a professional and I fear that they might think that my second job is not sufficient, because I will only have been there for a week or so by the time my partner applies for entry clearance.
Everything else is (sort of) in order, and it is really the finacial aspect of this application that worries me the most (always has, and now comes the moment of truth.. if my girlfriend gets denied it would render us broke!!)
I'm scared!
