[ivoke]

Well, from what i know,

basicly:

Twalen is black,
his sarong is black and white,
Petruk has green in his colorscheme and facial hair.
but he normally also has a bigger nose,so it could also be Delem,
my opinion its not Twalen or Merdah.

Gio's Hanuman has more features that could make it Twalen.

but this is my personal opinion, i could be wrong.
And i base myself on the Bali-Singaraja versions.