OK, a friend of mine suggested me to go with the same TRF as he mentioned the CO have all the necessary tools to check whether its forged or not, which isn't. If asked by CO regarding the spelling difference we can still show them the reasons by presenting my regional CNIC and explain the CO why it happened.
After submission of EOI, I can opt for IELTS again and get better results with a correction of name while I am relaxed and get more points to add into my EOI. I kind of liked that idea, and willing to go for it without any delay.
I think what your friend suggested is similar to what I said couple of post back, ryt? So I agree to that.
Also, you now have the email correspondence with IDP which would further establishes your validity.
I don't think another IELTS is necessary, rather you can have a notarized translation of your original NID with old spelling, plus an affidavit that you have changed your name spelling from this to that should be enough. DIBP might ask questions, but you have your valid cause.
Having said that, there is always a risk that they won't accept your reasoning (though I think the chance of this happen is slim). So, you can as well reappear in IELTS if you want. Also, if I remember correctly, you have 60 points, so it might be worth to try a second time to increase your IELTS score (a all 6 to all 7 in IELTS will give you extra 10 points, which is a big deal).