Obviously he hasn't.
If I owned a newspaper, I'd make a living out of publishing incredibly reasonable stories about Farage (i.e. nothing actually libellous, just untrue) and let him fume as the optics of saying "I never said I stood in solidarity with homeless orphans" aren't that grand.
Seriously, a paper should have published a "Farage apologises" fiction and let him sue them. Bearing in mind to be libellous something needs to be not only untrue, but detrimental to a persons public standing.