Although you can put an 8 speed cassette on a 9/10/11 spline, if the cassette body is made of aluminum
like most genuine Campy hubs, the shallow engagement will quickly ruin the splines.

I agree that the wheel shown is not a '99 and could be as old as '95. 9 speed came out in '97 and a Shamal from that year would have the new 9/10/11 speed spline, made of aluminum. If the cassette body is steel, it's a '95-'96.