They also showed that the cumulative genomes shed where higher for vaccinated birds vs unvaccinated birds when dealing with more virulent strains. And that this did influence the sentinel infections. Yes, that's due to death. It still shows that if mutations become statistically more likely with the cumulative genome shedding, then leaky vaccines do not prevent this and the genomic pool will be skewed more to the virulent side than it would have been otherwise. That's all pretty definitive. Now, does that definitely support that a specific outcome will occur, like vaccines causing more sereve strains- no.

Although this is kind of besides my point - that the two studies are not in conflict and perhaps the two parties are arguing two separate topics.