My recent experience may inform The Hood as to his next steps.
Ask the managing agent and committee for copies of ALL correspondence relating to insurance matters, say for the last 2 or 3 years. This should include
(1) emails to/from the managing agent and insurer;
(2) emails to/from committee members and the insurer;
(3) emails to/from managing agent and committee member; and
(4) records of phone calls of the agent and committee members with the insurer (and what was agreed/discussed).
It should not take long to discover the real reason coverage was denied. IMHO, coverage is declined because of something the committee or agent (on behalf of the OC) did or did not do. The records, if made available should answer this question.