Hello Piotr,
The Alb. word degë 'forking, crotch (of tree); bough, branch'
well reflects a PAlb form *dwai-(ga:) < PIE *dwoi-'binary, two'
Its derivation is the following:
PIE *dwoi-geh2 > [o>a;eh2>a:]> PAlb *dwai-ga: > [w>zero,ai>e] > degë
The same construction is reflected in OHG zwi:g 'id.' (see German
zweig)
So the word *dwai- (or at least *dwai- as root) really existed in
PAlb/Dacian?.
Please note also that the intervocalic g is not lost here (degë being
a bi-syllabic word) but was lost in *ragusa < rrush (tri-syllabic word)
Best Regards,
Marius
P.S.
Also please remember :) that the Romanian word for 'two' is doi and wa
> o is regular in Romanian...