O.K., let's review just exactly what you are doing here.
You are using simplePeripheral and connecting to the dongle. What is running on the dongle? You should be able to adjust the connection interval on the dongle if it is the Central device or you can adjust it through BTool if you are running hostTestRelease. The default is 100ms.
I'm not sure if you can get adjust the time for executing the event processing routine if there are events pending. Also, I hope you are not trying to do this when the keyfob is in the advertising state.
Thanks,