So, on my backup Android tablet, I wanted to look on facebook, installed it from playstore, I had some messages so clicked the link expecting to be forced to playstore, to install messenger. BUT, It downloaded it, and then installed it, and then it run it! Which is basically what I have been hoping to do for the past 5 years in B4A!
I'm going to presume that you have already enabled allow apps to be installed from other locations apart from the play store on your tablet. It should be easy enough to use JavaObject to check if that option/setting is enables/disabled on the current device. If the option/setting is enables then you can just download and install whatever app you desire, but if the option/setting is disabled you will be sent straight to the play store.
That is what I think is happening on your tablet, but I could be incorrect...