Actually it is none of the reasons above.
The Lexus 1mz-fe has vvt
the camry 1mzfe doen't they share blocks and sintake manifolds but not heads. That is where all 1mz engines differ.
Can you make it fit, yes .
Will it work properly, i have no clue but i would fathom a guess trd would ahve tried it first but backed off the app as it wouldn;t run right for a production toyota part for a new car.