It is an interesting question. Looking at Clause 61.4, the Project Manager may decide if a notified event is not a compensation event stated in Clause 60. It it is not stated in Clause 60, the Project Manager notifies the Contractor that nothing is going to be changed. However, if the Project Manager believes that the event meets the requirements under Clause 61.4, he notify the Contractor to give quotation under Clause 62.
Thus once the Project Manager decide that it is a compensation event and ask the Contractor to give quotation, there is no provision for the Project Manager to reverse his decision. If the Project Manager insists to change the decision, it constitutes another compensation event under Clause 60.1(8).
And I think you are right, the Project Manager is allowed to make his own assessment under Clause 64.1 bullet point 2, although it is not suggested as it breach the spirit of mutual trust and cooperation. I believe you should look into the Contractor's quotation regarding the compensation event. Check if he could demonstrate his loss and if affirmative, you should consider to take his quotation into account.
Thus once the Project Manager decide that it is a compensation event and ask the Contractor to give quotation, there is no provision for the Project Manager to reverse his decision. If the Project Manager insists to change the decision, it constitutes another compensation event under Clause 60.1(8).
And I think you are right, the Project Manager is allowed to make his own assessment under Clause 64.1 bullet point 2, although it is not suggested as it breach the spirit of mutual trust and cooperation. I believe you should look into the Contractor's quotation regarding the compensation event. Check if he could demonstrate his loss and if affirmative, you should consider to take his quotation into account.