Ask the GC
(1) Which "LEED Credits" they are trying to obtain,
(2) What they want you to do, in order to assist in being awarded those credits, and
(3) What records they want you to produce, in order to demonstrate that the requirements for getting the credits have been met.
A common misunderstanding is that nobody gets LEED Credits or gets certification at any level, unless the project is registered with the US Green Building Council, and unless their fees are paid, and unless documentation is submitted to prove that credits have been earned, and unless the USGBC itself awards the credits.