The Problem here is the big picture, its not about whether temperings are in an event or not, it also matter what the event is and who can reasonably expect to profit from it.Yes you aren't forcing anyone to participate but that excuse can be made for literally everything you do and is kind of mute. Events are the most efficent way for you as admins to adjust the ingame economy, ballancing etc. so when u use it you should also take into consideration what effects it will have on those variables.
So yes, due to many ppl reaching the same level of gear temperings went up in price by a lot really quickly and correcting for that would help a more stable economy and the overall ballance. but this event is badly timed and chosen for this cause:
A. target group is already endgeared maxed pvp players which currently really dont need another boost.
B. Tempering prices may go down but the profit will be just pooled up in the same top players wallets so the overall economy just shifts even more towards them.
C. Instead of making it possible for medium geared players to just get the tempering, you are now forcing them to keep buying them from the players who already have billions in wh.
D. since everyone and their mum is now in need of kinah (as its the only way to get those temps unless u are zerging or got a pocket cleric and 5*) the E coin value also drops to the floor with current prices coming out at 10-13+€ per tempering even for those willing to donate in order to gear up. (elyos)
The initial impuls of adding an event with tempering is great but it would have had to be one where the nubs can also get them, some kind of collecting shit or shugos or lottery or whatever crap would have worked as long as the tempering and entchant stone supply gets split across different gear and exp levels. That way you would:
A. Keep the economy ballanced since the supply and demand for temperings would match more closely. (edit: I hope you are aware but the price for tempering on elyos side was stable for over a year before, so this is actually quite reasonable to expect)
B. give new and gearing up players a chance at a starting fund from participating and selling. (temperings in events and drops are generally the best boost for new players as it brings in enough kinah to actually make a difference at most any step of gearing)
C. give those who want tempering two options of either cashing in or grinding the event.
D. would still get a boost in ecoin sells since many will chose the first option. (this includes me, I was all willing to spend a couple bucks on this since I work more atm, but the proposition of ~13€ a pop for temperings is just ridiculous)
E. the likelyhood of high end players stockpiling the Temperings would be lowered a lot. (the same people as always will be keeping their temperings now expecting prices to go up again after the event, making the current prices artificially higher as well)
F. give both sides equal chance of catching up with gear.
so yea no idea how this shit isnt obvious tbh. but maybe just think of the overall impact you have with the event design next time instead of wondering afterwards why the changes you made aren't seen as good by your players, try to understand WHY they ask for something instead of just giving them whatever they shout for the loudest.
oh btw. overall I think you are doing a good job with this server, just in regards to events you still seem to get it wrong quite often in this regard.