Well yes I agree
@Veritas - it hinges on the likely outcome of a re-assessment of his capacity to manage his finances, but OPs description of what happened when his capacity for managing his finances was made make me feel that if this were reassessed it is highly likely that he would be found not to have capacity.
If his re-assessment of capacity demonstrates that he does not, in fact, have capacity to manage his finances and the person who assesses it is willing to sign the COP3, then
@MumblesPat can apply for deputyship which is likely to be a simpler and quicker route (she can request fast tracking)