A gold reward that can be easily split between guild members is still the best fair solution. Buff rewards can affect character balance and occasional events, so the only solution would be gold/drop buffs. Item rewards, on the other hand, have often caused disagreements within guilds/unions in the past, and we've often heard about that in Helpdesk reports.
As places to get the Trophy, these will most likely be:
Kaligo - for weaker players (with the planned change to party buffs in Chaotic Frontier)
Tesseris/Tesslon - for guilds and stronger players
Lydia - challenge level allows both weaker and stronger players to get it
If they were to be introduced in the drop of regular monsters (Infernum, Shinewood), the chance of obtaining them would be much lower. We will leave this for discussion. We may change the rules every month or so to test different solutions.