I think you have a mistake in one of your linq queries:

                   // get list of open issues with matching history items for the project using LINQ                 
                    var tmpIssues = from Iss in issues
                                    join st in StatusManager.GetByProjectId(p.Id)
                                    on Iss.StatusId equals st.Id
                                    where st.IsClosedState = false                // SHOULD BE ==
                                    select Iss;

However, fixing that exposes an additional problem where an error is thrown when searching comments. I couldn't track that down, but I think it has to do with the delegate for GenerateIssueCommentListFromReader