In my mediation analysis, I run a multi mediator analysis and in the output of AMOS I cannot find the third indirect effect (the path from X to Y-Q-Z). Can you explain here, how can I find this value?
I suggest you to use bootstrapped multi-mediation analysis for your proposed model. Specifically, one of the most acknowledged techniques is Hayes' PROCESS macro (which runs on SPSS); the template you have to assess refers to MODEL 6 of such a macro, where you have 2 mediating variables.
In this way, you'll be able to check not only statistical significance (p-value) but also practical significance (confidence intervals) of direct and indirect effects.
Download it freely here: https://processmacro.org/download.html