Well, i'd tell your friend to stop using Brasso on his blade.
Panjang at know, yes, for it's long length, but also for this particular style of features. These are indeed the blades that are referred to as "executioner keris", but this does not mean that this or any other pajang you see was necessarily used in that manner. AFAIK the panjang is a status keris so perhaps those who had the status to wear them also had the authority to execute. Maybe someone can clear that up for us.
Jawa Deman roughly means the fevered Javanese and is a reference to what appears to be a representation of a figure, perhaps double over in illness. I am not convinced that this hilt was ever intended to represent Garuda, though i have heard it referred to as such.
Your friend's seems to have some age to it and while i think it's pretty impossible to put and actual age on this i'd say that it is probably late 19th - early 20th century.