charlie time to tease a little more information out of you
1. did you actually see
v3.20.3 as a part of the updates you were installing, or do you understandably assume it was there?
2. do you have an icon on your desktop, maybe in panel or system tray, for HP?
3. do have Synaptic Package Manager available to you?
what i think has happened is this, more or less.
the HP stuff includes its own automatic updater. v3.20.3 is still hanging around HPs Developer Portal.
your output from apt-cache policy and apt show indicates you have
installed, and i have checked on a live tricia mate stick and it shows that 3.17etc was the version it installed with, there have been no updates since (through the mint repos)
if you can confirm on the above questions, we can go from there, and jg @jglen490
as a fellow HPer to you might say whether i am crazy.
no, apt-cache policy or apt show is the go, as i explained.
and also nope
sorry, 2 strikes
can't install debs using apt
gdebi can be used, or its GUI gdebi-gtk (from FM)
sudo dpkg -i /path/to/name_of/package