Dear Nick Jay,
as discussed in the post PMI Calculation, knowledge about the power allocation of the transmission is not available in the calculation of the CLSM feedback. The power allocation for transmission is set after the scheduling of the users, which can use the information from the CLSM feedback for the scheduling information.
Therefore, it is likely that you have no other choice than to assume uniform power allocation in the calculation of the CLSM feedback. If the scheme you are implementing allows a more accurate estimation of the transmit power that will be scheduled, then it is advisable to use your own implementation of the more accurate transmit power to be scheduled.
I hope this helps, best regards,
Agnes