Possibly. Has your H1 been approved? www.immigrate2usa.com

How much time its taking now days for I-140 approval for EB1 Multinational Manager category ?

several months.. up to 6 in some cases check www.uscis.gov or www.immigrate2usa.com

Do I have any issues re-entering the U.S. or reapplying for a J-1 visa as a non-US citizen given unpaid debt in the U.S.

Your debt should not be an issue, though it is possible you have a default judgement against you www.immigrate2usa.com

I am on F1, school is no longer SEVP certified and my H1b is under process. Can i stay in US till my H1b gets approved?

More facts are needed, but you may want to consider premium processing www.immigrate2usa.com

How does someone whos case was complete after mine at NVC get a interview schduale before me?

You should ask NVC. The wait times depend on the consular post www.immigrate2usa.com

US citizen sponsoring parents. Already filed for form I - 130 and got receipt. Parents are in US on a multiple 5 years visa,

I agree. Filing I-485 is best and fastest bet. They will need advanced parole to travel For more info www.imigrte2usa.com

Greetings. Is there a reason why my family based I-485 got transferred from NBC to NSC?

I agree , this should not be a problem

H1 VISA related. Please see details section.

Your employer will need to file a new petition but according to USCIS you have been countded towards the cap www.immigrate2usa.com

I-539 one for change of status and another for extension

If there are two COS, USCIs will be confused. I am confused to know how you had H-4 and H-1 www.immigrate2usa.com

DACA Question

I agree , you do not need to put down the tax ID www.immigrate2usa.com