Delay in H1-B stamping and change of employers


I went to India to get engaged in Mumbai and get H1-B stamping with an approved I-797 (filed in regular). The visa interview was on early XX Jan’12. However, I got a 221g White. About 2 weeks later, I was informed to submit certain documents including client letter,EE relationship etc. It took about a month to get all the documents from the US and everything was submitted to the VFS office. After this, there was no update at all from the Consulate as the months dragged on. Finally after waiting till mid-May’12, I was totally frustrated and resigned from the US company and took a job with a very large Indian IT company. The strange part however is that about a month later in mid June’12 my US employer got an update from USCIS and me from VFS that the documents submitted late Feb’12 have been verified and told me to come to the consulate with the passport and other documents. I contacted my previous US employer and both agreed it would NOT be the right thing to go with the passport and documents for the visa stamping (The separation from the US company was cordial and done properly). I have not replied or actioned the letter from VFS.

I have the option of joining his US employer again but at the same time lose a very good position with my current Indian IT firm having global operations.

What are my available options in this Catch-22 situation?
Do I have to respond to the letter from VFS? How and what needs to be done.
Can I go with my documents once my US employer agrees and sends formal documents for re-hire or do I have to file a new petition all over again even though I have an approved I-797 from the same company for 3 years.
Can something be done by my current Indian employer.

Please advise and throw some light if anyone has faced such a situation or know about it.