Sticks & Stones - Inscribed Shards

Drop rates really really suck on these shards on my accounts. More than a year ago, I got the Sticks & Stones (NF) quest on a character. After spending more than a week, I gave up trying to collect the Inscribed Shards. During that week, only got one. I am now trying again on a different character. I have spent most of the past 5 days, a good 40 hours, trying to get the needed shards. With the one from a year ago, I have 4 total shards. I have farmed the "A Show of Force" quest over and over, and moved from zone to zone trying to find these shards.

I am Ranger, using full hero team. Have gone from low R4 lightbringer to med low R5, just farming the shards. I need some ideas on how to get the shards to drop.

Have all campaigns, all heros minus the 2 sins and Razah, all skills unlocked for heros.

From The Mouth of Torment use SW exit. Move NW to the northern entrance to Crystal Overlook (15-20 targets in this area). Once in Crystal Overlook cross over bridge and down the hill (south) (8-10 targets in this area). Return to Mouth of Torment useing same route, repeat.

Ran into an old friend ingame, he had a few and he helped with a Spirit Spammer. Just 2 of us and got the drops in 2 1/2 hours. He was surprized at how long it took.