Download and install all desired versions in such an order, that the last version downloaded and installed, is the version that you would like Tableau Desktop to launch when opening related files (Tableau Releases).
Example: You want to ensure that all Tableau files default to opening on 2018.1, AND you want Tableau Desktop 10.1, 10.3 and 2018.1 on your machine. Install 2018.1 last.
If Option 1 does not work as expected, set your machine's default program (associated with Tableau file types) as the version that is desired:
Click Change All, then Continue if Finder asks to confirm
Tableau Desktop will default to the most recently downloaded and installed version when launching related files, even if it is older than the version in which the file was made. It is also possible that the machine cached information for a previous version can be kept as a default.