I checked again, you are right. they called in time. but this doesn't resolve the basic problem (the most obvious) - P. cleared both on same level and then didn't observe what was going on. Clearing DHL to fl340 would be the easiest solution. but we can debate about the reasons why P. didin't do this, the fact is that passengers are dead and so is he. Don't get me wrong - I'm not blaming P. for being the the only responsible for the crash, but it is not fair from ATC community (to which I belong) to point to all other factors except this.