My brother is a mechanical engineer who took the path you're planning to take. You can surely do ACM from NICMAR. Although, I will recommend that you do it from the Pune Campus.
It is better in terms of Placement opportunities available. It is more diverse and will help you in being exposed to varied perspectives.
A lot of opportunities await you as a Mechanical Engineer in the Middle East in HVAC and in the MEP Departments of Construction Companies.
Both RICS and NICMAR are reputed. On an overall scale, NICMAR will be a better option. It has huge contribution in the construction industry of India.
NICMAR Pune placements are pretty good. You will get opportunities to join reputed MNVs, Contractors, Banks, and IT companies. According to the recent placement highlights, the Real Estate Urban Infrastructure Management had an 100% placement rate. Some of the major recruiters that visit the campus placements are ITC, KPMG, Goldman Sachs, etc. The average CTC offered by the institute is INR 6.75 LPA.
In the construction management sector, NICMAR is a well-recognized brand name.