Sitting here for a long while, jsut can't seem tog et this one, solved everything else on the map.

Same here, can't figure it out.
Even looked online for the solution and followed it, but it doesn't work for me:
https://www.ign.com/wikis/thronebreaker-gwent/Aedirn_-_Side_Quests
I can destroy 2 of the four spotters before I play my last Arbalest, but if I then destroy the topmost spotter - leaving the one at the bottom unalerted and at 6 Health - I lose upon passing.
I might suggest, that thats a bug and not a feature?!

I tried leaving one at bottom, it's easy to do, you lose that way. Tried killing them in one blow, but one of spotters stays at 1 health, in theory it shouldn't move since no one on the row at a time. Either we both can't see something or it's a bug.
I gave up and moved on.

I tried every combination and I'm afraid the puzzle is bugged since it absolutely does not work. The spotters have 24 health yet the maximum you can damage is 23 hence there is always one spotter with one point left. You can also not isolate a spotter on your ranged row because that will lose you the game. The Solution to get to 23 is to first place the trap in the ranged row of your opponent, giving the first spotter -2, afterwards you place your Wagenburg in your ranged row, thereby activating the spotter in that row to move up to your melee row, he is now on a row with another spotter. You then place an Arbelast and shoot at ther already injured spotter, giving you another -2 for -4. He is at 2 now. Next the Spotters will move together into the melee row, so you have 3 of them together. You now have 1 spotter at 2, and 3 spotters at 6. Next you place your Sapper and hit the injured Spotter and take him off the field and get another turn. That makes -4 bringing you to -8. You have 1 Spotter at 4 and 2 Spotters at 6. They now all move to the melee row and take trap damage of a combined -6 that brings you to -14. So you have 1 Spotter at 2 and 2 Spotters at 4. You now deploy your Arbelest giving you -4 and eliminating one Spotter with 4. Thus you are now at -18. Your Wagenburg is now charged with 3 and that's the problem.

If you have been counting you now have 2 Spotters. 1 with 2 and one with 4 but your charge is only 3. So... yeah. So you hit for a combined 6. That actually brings you to 24 BUT since one Spotter is at 2 and the other is at 4 you waste 1 point. So you only get to 23. I have tried it countless times in different setups. Even is you place the Wagenburg in your melee row to get another charge from the moving Spotter it's no good because you need to actually move one of your units to the ranged row to get the Spotter moving otherwise it just stays there. And you need to eliminate it. Also if you try and do that you will have a massive problem because you won't have the damage points to stop the other 3 Spotters from escaping.

So yeah. I have tried every combination I could think of and I have spent easily 5 hours on this puzzle, I have done the maths and unless I have totally messed something up I don't think the puzzle is solvable. I think it's bugged.

So yeah I agree... Probably bugged to hell.

best I could come up with one left with 1 point as well, no way yet to knock em all out

same here, either can't kill them all (like one stays locked in the lowest row) or at least one escapes with minimal power

need help with this one please

thanks