@yonnyvan, I get your point, but I think you are missing my point about Clashes overall. They have nothing to do with who your club gets matched against, just how many points you can accumulate. They have little to do with who is better or has more skilled players, and the prize structure is ridiculous. It's purely a money grab by WGT to drive participation which leads to increased ball/pass purchases. Not that there's anything wrong with a business trying to make money. That being said, if you still want to boost your club participation here are a few things you can try:
Educate your members that it doesn't matter if you are loosing 25,000 to 100 in a particular 4 hour session, they should still play a round when they are available to help add some extra points to your overall club total. All that matters is YOUR club total, not anything else. Not who you play, not how many of the head to head matches you win, nothing at all except total points!
Try setting a club goal for how many points you can accumulate in the next Clash. Don't pay any attention at all to who you are playing, or how you are doing on the grand leaderboard overall. Just focus on how many players participate and how many total points you rack up by the end.
Then, a few days before the next Clash rolls around, make an announcement to your members about how many participants/points you previously had, and how you'd like to make it a team goal to surpass that. Maybe offer some type of trophy or a small monetary prize to the top point earners. Could be some sleeves of their favorite ball, a piece of apparel of their choosing from the Pro Shop, whatever you think your members would be interested in - the prize itself doesn't really matter as long as it stirs up some competition to get folks to participate.
Offer to donate CC passes to anyone who would like to try it out but are afraid of whatever - that way they aren't losing anything other than +/- 20 ball hits and about 20 minutes worth of their time. Offer a prize pool for the daily/weekly club goals that earn you extra Super Passes. These are all just little things you can do to improve participation.
If you want to get a little more drastic you can start recruiting here and/or Discord for Clash players. Make it a requirement that every club member plays at least one Clash round every 2 weeks or face being bounced out (I don't personally recommend this, but you asked for ways to boost Clash participation).
You can pick and choose any/all/none of these ideas - you know your club members better than I do. You can also expand some of these ideas into other areas of your club other than Clash to help boost participation. Keep doing this time after time and I promise your numbers will slowly go up, both in total participation and leaderboard ranking. It will be a long, slow climb, and at some point you'll likely max out your potential, but I promise you the Penalty Boxes and Kelly's Heroes of the world weren't built overnight.