Do I need to report the grandparent's 1099-Q on my tax return to track it under the 1099-Q section as participant being "another person" for Room and Board for student.

Q. Do I need to report the grandparent's 1099-Q on my tax return?

A. No. Do not enter their 1099-Q.  But you must coordinate with them on the allocation of expenses, to the 529 distribution, tuition credit (on your return) or to scholarships.   You do that manually.  If their 529 distribution was used only to cover room and board, there is no coordination needed (unless you also had a 529 distribution) since r&b are not qualifying expenses for a tuition credit or tax free scholarship.