our esteemed VBD is far better qualified to deduce this than moi.
I took out all non-lowland riders. Took out the youngsters. Took out Boonen's right hand guys Cretskens and Hulsmans.
I think I should have added in Addy Engels hey VDB.
I added in Vasseur, a non-lowlands rider as far as a know, thought traditional Flanders does encompass modern day France. (some of)
I just knew Van Impe had come along slowly, and came from a famous cycling family. And left the guys in I did not know much about.
I pegged it for Tankink, with a very pissed off Bauet and Vasseur, because those guys will probably get fingered too in the internal witch hunt.

ironic. Hunting the whistle blower, and not the doper.
The list tallies with your reasoning, but I'm not sure the article leads to the above qualifications.