Investment in the fd's of private company

Yes, It can invest into FD Scheme of Private Company.

You need to have all sanctions / permissions from the Trust to invest the money.

The Company should be CRISIL / ICRA / CARE / Fitch / S& P accreditated coompany.

Higher the ratings of the company, it will more safe & secured to invesments.

Kepp FD for 1 year and see how they give service, then think on long term investments.