Thank you for your reply Prof. Pfeifer.
Then it was as I suspected with the conditional welfare.
If I have understood the code in
evaluate_planner_objective.mcorrectly then it is line 74 that is of interest
Wss = beta*Wuu*M.Sigma_e(:)/(1-beta);and the solution would be to either remove the \beta from this line or to add \beta to my manual computation for a proper comparison to be made.
(The odd welfare ranking was an unrelated problem that has been solved.)