From the information you have provided from the installation log file, it appears that the installation of R2019b was successful but the shortcut to start MATLAB may be corrupt or contains an incomplete path.
To create a new shortcut to open MATLAB, navigate to your Applications folder and right-click or CTRL+click the icon for MATLAB R2019b, and select "View contents". From here, there should be an executable to open MATLAB R2019b. Try opening MATLAB from here. If this opens successfully, you may create a shortcut by doing the following:
You can add MATLAB to your Dock or you can create an alias.
- To add MATLAB to your Dock, simply drag the application onto the Dock and wait until the other icons make room for the MATLAB icon. Then release the MATLAB icon.
- To create an alias, right-click or control-click MATLAB in your application folder and select “Make Alias.” The alias will be created in the same folder MATLAB is in, so you need to move it to where you want it to be.
DISCLAIMER: These are my own views and in no way depict those of MathWorks.