I`m quite convinced no pedal will do the job. Maybe if you go midi guitar you might
find something, don`t know about the Roland VG88 either.
There are pedals manipulating pitch bends but don`t sound like the sliding notes on
a fretless oud.
Using a standard el gtr the closest I can think of would be a clever combination of slide,
maybe ebow, EQ to simulate gut strings ;-), a little compression and some smart reverb
or short delay to simulate the oud body.
The recipe doesn`t sound very convinving though. :_)