Checkpoint has discontinued (official) support for their
snx client, on the Linux command line, a couple of years ago.
snx has not been supported from the command line after version 800007075 (from 2012) ; newer versions only work officially when invoked from a Java Applet, supplied when browsing the Checkpoint appliance.
Per my post, that you are linking to in your question, 800007075 is the last one having the routines for doing the VPN full setup/configuration in Linux/Debian derivates from the command line. Maybe my fault, in that I am not entirely clear on that.
snx version 800007097 you are using, won't work, when trying to connect to the VPN from the command line.
Newer versions might work, with
snxconnect to complement the missing routines in the newer snx versions (hence the python tools), however the reverse engineering of the missing
snx functionalities still presents some peculiarities. So, I recommend using the older version, that does not need the python tools.
I have been using
snx version 800007075 for months now, with Debian Stretch, and it has been working pretty well.
The 800007075 works without the
snxconnect python instructions. The newer/your version needs the python hack/tools.
For using the CheckPoint
snx program in the command line, without the python tools, you do not download the snx client that comes with your firewall appliance.
You have got to download the old 800007075 version, separately from here https://starkers.keybase.pub/snx_install_linux30.sh?dl=1
; then follow getting Checkpoint VPN SSL Network Extender working in the command line, for setting it up with more modern version of Debian derivates.
PS. A workmate using the version of Ubuntu your Mint is based, followed my instructions last week using the
snx version 800007075, and has been working fine. (as mentioned, I am using it myself in AntiX/Debian Stretch)
PPS. Taken from the Arch Linux AUR repositories scripts Package Details: snx-800007075 800007075-1, you can also get the 800007075 Checkpoint VPN client at https://starkers.keybase.pub/snx_install_linux30.sh?dl=1
PPPS. The link in this answer for downloading the VPN client does not working anymore. Edited to replace it with the link mentioned in PPS