Don't, Don't, Don't
Elmo is a fibber and a drubber and a jock. He's whispered to horses and conversed with dogs. A diamond in the rough, he is, but no pinhead.
The Role is The Tickler.
I couldn't figure out the Elmo clue but... duh! Tickle me Elmo. And what does the victim of tickling or "Tickling" say? Don't! Don't! Don't!
Tickler it is!
The actor is almost certainly Anthony Morris.
Drubber = He played Drubber Dockery in Trouble in Paradise.
Liar = He played Anto in Little White Lie.
Whispered to horses = He played Traveler #1 in an episode called The Horse Whisper on a series called Kllinaskully.
Conversed with dogs = He did a voice on Family guy where he likely talked to Brian.
Diamond in the rough = He played Billy Tiernan in the TV series Rough Diamond.
Jock = Billy Tiernan was a jockey.
Not a pinhead = the most famous Zippy the pinhead. He played Zippy in Adam and Paul
And his agency page confirms he will be in Season 2 of Game of Thrones.
You guys are just too good.
Yes, you've nailed another one. It's an Irish actor named Anthony Morris, and he will be playing the role of the Tickler.
Is there gold in the village?