If something is submitted to the PM for approval and the PM approves it then there is a risk that liability may have changed from Contractor to Employer. It may be unlikely though as it’s clear from clause 14.1 what the intent was, see also clause 12.3 and presumably the Employer has stipulated in the Contract Data that the Contractor has to provide professional indemnity insurance.
Others may be able to give a legal analysis of this issue, which would be interesting but I suspect would result in a similar opinion that the conduct of the parties may cause a problem.
If you are the Contractor finding yourself in this situation then ensure that you submit things for acceptance, not approval, unless you are deliberately attempting to shift risk (see clause 10.1 please!). If you are a PM asked to approve something, do not do it, merely accept or reject or risk being in breach of contract with the Employer (if you are a consultant PM with a reasonable skill and care obligation).
Your suggestion is the best practical solution, firstly this matter should be an early warning matter so you can flag up the problem and resolve it by getting the PM to issue an instruction clarifying that where the WI states “approval” this means “acceptance”. Unless of course this wasn’t the intent of the Parties, in which case a Z clause should be used to amend clause 14.1 to reflect what the Parties thought they had agreed.