Is NICMAR a worthwhile investment for a graduate civil engineer?

I suggest you give one more attempt at the entrance exams if your age permits. Otherwise, if you are planning to take admission this year itself, then you can choose NICMAR. 

NICMAR is a reputed institute with good placements. The highest salary goes to 16-17 LPA and the average ranges to 7-8 LPA. Irrespective of your undergraduate, you can learn and gain management knowledge. 

There are many companies in the corporate industry that prefer civil engineers for management roles, so you can grab a good placement for this college, and you can also participate in various case competitions organized by various companies and grab a placement from there as well.