Ok, so I came up with a quick and dirty fix. Very dirty.
I only share it for educational purposes or if someone like me is stuck...
I tested it successfully last night, but use it at your own risk ;-)

So basically what I did is write a small Bash script that is cron'd to run every 5min:

  1. It checks if the mount status is parked and not tracking, that could mean it is either truly parked or slewing to its parking position
  2. Then it waits to see if the mount status changes to parked and tracking
  3. If it is, it issues a park "command"
printlog() {
  timestamp=$(date +'[%d.%m.%Y %H:%M:%S]')
  echo "$timestamp $*"

printlog "Waiting 10s checking if mount parks"

indi_eval -t 10 -wo '"Losmandy Gemini.TELESCOPE_PARK.PARK"==1 && "Losmandy Gemini.TELESCOPE_TRACK_STATE.TRACK_ON"==0'

printlog "Mount is parking or parked: Waiting 60s checking if tracking restarts while parked"

if indi_eval -t 60 -wo '"Losmandy Gemini.TELESCOPE_PARK.PARK"==1 && "Losmandy Gemini.TELESCOPE_TRACK_STATE.TRACK_ON"==1'; then
  printlog "Tracking restarted while mount parked: Reparking"

  indi_setprop "Losmandy Gemini".TELESCOPE_PARK.PARK=On

printlog "Mount parked"

exit 0

PS: Especially for resource usage, I should be adding an if condition on first indi_eval, but haven't tested it yet...