Drive Shaft Problems

[cts1986]

hi guys hopefully somebody can shed some light on this for me.

my t sport began vibrating through the car so had car checked, after checking wheel balance, engine mounts ball joint and bushings it was diagnosed as a driveshaft problem, as under power it vibrates at any speed, and not accelarating smooth, now i have purchased a drive shaft off another t sport, but the guy sold it to me without the inner cup that has the splined shaft that goes into transmission, so i just have boot with bearings that goes into the cup in the tranny, is this correct??? should he have given me the inner cup with shaft on it as well?? any help please