Despite everything, IIM Calcutta is a much better business school overall than IIM Lucknow, regardless of the field. However, if you do not receive an offer from Calcutta, you may consider Lucknow. Some companies may not shortlist you because there will be candidates with far superior academic credentials. However, this is not a sufficient reason to avoid attending an IIM. You will have numerous opportunities to enhance your CV within the b-school through academic performance, winning b-school competitions (which often leads to a direct PPI), participating in PORs and other extracurricular activities, live projects, and so on.
Regardless of your prior academic performance, you will almost certainly be better off with an MBA from IIM Calcutta or Lucknow than without one, assuming you don't waste the two years in b-school doing nothing.