I think the two things have nothing in common. I mean, sensu strictu, yes, obviouslly. But in that case, actually you could say almost anything strenthen tanking. Even the OET, if you tweak the argument, strenghtens tanking, since draftees are now really really valuable, then been in the highest possible draft pick would also be really valuable, and to get there the best way is to tank.
It has nothing to do one thing with the other. Besides, you commit the error of thinking that only first place teams would be in the OET. I must address you, for example, to the top league of my country, LUB-1, where the champion six years in a row has more than 600k in tax exemption. Or even my own league: right now I'm leading, with a 103k tax exemption, and the guys in 6 and 7 place are in red numbers and paying the OET because they have no trainees.
Tanking has its own "strong" arguments, regardless of the OET or of this suggestion I made. If you want to eliminate tanking, you should think about a Draft Lotery, or even a Draft Fixture, to begin with. Do you think a top pick from tanking is not "reward" enough? And what reward would the tankers get if no one goes into the OET?
As I see it, the suggestion I made rewards people that DOESN'T go into short term, and doesn't get into OET. But only does so if there are players in the short term and going into OET. I hardly see any real, pragmatic connection, rather than the theoretical one you mentioned, between the tanking and this.