Even i don't believe Lauri getting traded at least not yet.
But Ainge's nickname ''trader Danny'' so there has to be a reason why Ainge has got that nickname.
Only scenario where Lauri might get traded is that Jazz rebuild will take longer than expected and Lauri's prime do not fit Jazz timeline.
And if Ainge really wants that 3rd overall pick so badly he'll find a way how to make that happen and it not necessarily mean trading Lauri.
Jazz has players like Clarkson, Gay, Azubuike, Toscano-Anderson, Fontecchio etc who aren't fits to Jazz future so trading two or three guys of those in 3rd overall pick should be possible.