When you say you swapped the relays(hrw and fan), was this the relays in the under steering wheel fuse box?
There is another relay under the bonnet which switches the fan on and off. It's the yellow relay beside the under bonnet fuse box. It's possible this one is the issue.
By the way WD40 acts as an insulating coating when dry so is not good for electrical connections!
Get some electrical contact cleaner instead.
On Fs the two fans are controlled independently; the engine fan being controlled by the sensor above the coolant expansion tank. Disconnecting that sensor with the ignition on should start the fan.
Make sure both fans are rotating freely by hand. With the ignition off obviously!
Youcan use your wd40 on the fan spindles if they are stiff.
Let us know what you find.