If you type meanPath = Mean[simData] you get the global mean, just one number. You need to map the mean to the values at the various times:
meanPath = Map[Mean, simData["ValueList"]]
Similarly for Quantile:
lowerBoundPath = Map[Quantile[#, 0.05] &, simData["ValueList"]];
upperBoundPath = Map[Quantile[#, 0.95] &, simData["ValueList"]];
