National Insurance Academy- NIA

The CMAT cutoff above 80 can be good enough for NIA Pune. Hence you have chances here.

Following steps are common to all candidates applying for admission to BITS Pilani :Apply for BITSAT (BITS Admission Test). After all applications are recieved, exam center, test date and time allotment starts. Candidates can download Admit Card starting from probably first week of April. (. Appear for BITSAT.

Candidates selected by any IIM for admission are informed through email which also contains the 'acceptance of offer' form. The candidates have to confirm their admission by filling the 'acceptance of offer' form and making payment of an acceptance fee within the stipulated time frame. The admission is confirmed by April-May, on completion of other formalities and payment of first instalment of the tuition fee.

Your class 12th marks have very much importance after 4 years of engineering during job because while your job is considered, during your interview each and every qualification that you have taken is considered and good marks show your hard work, Talent and Dedication towards your study and your seriousness about your career.

I would suggest you to try for another college as many colleges accept 69 percentile. Many colleges have their own entrance test, as last year's cut off in NIA was around 75-80 and this year it would be from 70-75.
Here is the list of top MBA colleges apart from NIA:
1.ISBR Business school Bangalore
2.Acharya School of Business Bangalore
3.FIIB MBA Delhi
4.Alliance University MBA
5.Christ University MBA
6.Symbiosis MBA School
7.IFIM-Business School
8.ISBM Pune
9.ITM Navi Mumbai
10.ISME Bangalore

There is no other way to get an admission in NIA.
CAT / CMAT score is mandatory.