You are right that the probability that a vaccinated infected person is asymptomatic is greater than the probability that an unvaccinated infected person is asymptomatic. But the probability that a vaccinated person is infected and asymptomatic is still much less (at least two decimal orders of magnitude less) then the probability that an unvaccinated person is infected and asymptomatic.

So the logic they’re using to choose their targets is valid - the issue is whether they should be choosing targets at all.