Following the ending of "The Hotel Inspectors", the hotel doesn't seem to have suffered any serious adverse consequences in the next episode. One small change is that the fire alarm control has appeared in reception by the time of "Gourmet Night". Since the entire worry about inspectors was started by a second hand rumour overheard by a friend of a friend, it's possible that the inspectors were nothing to do with customer service and were simply carrying out a basic fire safety check.
The series ends with Basil trying to bullshit a rat infestation past the health inspector. They failed the inspection and got shut down.
Manuel is from Barcelona - so he speaks Catalan.
In "The Germans", they don't call "999" and just take out the fire extinguisher. It makes sense why they didn't - they were panicking.
In March 2014, The Daily Telegraph wondered if "the abject Spanish waiter Manuel" was a political refugee from Francoist Spain. Whether this counts or not depends on how many more mass graves are discovered.
Given as he frequently refers to his (living) family back in Spain, with whom he is in regular contact, probably not.
"Basil the Rat" ends with the health inspector discovering a rat in the hotel after what was already a fairly poor report. Perhaps that's why there was never a third series.
Failing that, Basil is dragged off (out of view of the Health Inspector), perhaps the stress of the situation culminating in the man seeing the rat in the biscuit box finally gave Basil that stroke that O'Reilly warned him that he'd end up having.
