I will give you an insight into both the options you mentioned, i.eMBA from IIM or Bootcamp.
Bootcamp: If you are very passionate about Data Analytics then Bootcamp is the best option for you. I deem this course better than an MBA from B School as a B School covers various arenas of Management while Bootcamp solely focuses on what you are looking for. Moreover, you will end up paying hefty fees and will have to pay loans for years. It provided a detailed approach to Data Analytics and you don’t have to study irrelevant topics
B School: B schools like the new IIMs are good for people who are not certain of their career interests. In that case, B-school would teach you much more than Data Analytics, and then you can pursue the field you excel in or are most passionate about. The excellent pedagogy of IIMs enables you to inculcate skills like handling a project, building a workforce, execution, etc. Basically, you are groomed on an overall basis and get industry exposure as well.
I have seen many people pursuing MBA and also online courses that offer Certification in Data Analytics specifically. So that is also a viable option for you.