The standard is front to back but with a crew member serving from each side of the trolley I can see how rows behind you could be served before you, I’m afraid that is just how it is.
The crew in the WT Plus cabin also serve the WT cabin behind and after delivering the special meals in your cabin would have delivered the special meal there before commencing the WT Plus trolley service.
Tea and coffee should never be cold, the pots that they serve from are thermally insulated.
The suspected food poisoning on both journeys seems very strange?