As has already been discussed, the main issue was the paying Shard(s) and getting an empty chest. The reroll-counting-towards-ransack was kinduva collateral issue that rode in along with the main issue. And to a much lesser degree, being allowed to pay to reroll an empty chest at all.
Since you can only reroll a chest once, it really doesn't matter to me whether it adds to Ransack or not - as long as everyone knows which way is WAI. What *I* think should happen, is deactivating the reroll option as soon as a chest reaches ransack warning. But that's just me.
As for reimbursing the few Shards I used - thanks for the thoughts guys, but seeing that my effort actually made something happen within the big hamster wheel behind the curtain is cool enough for me.
This bug is akin to stepping into a quest then stepping out and resetting before completion of the quest counting as a completion for purposes of XP and daily bonus. It really is a pretty bad bug and ought to be fixed post-haste. I wasn't even aware of it until I saw this thread.
I believe that haverdasher should be the comparison as the other chest in the miller's debt 100% on a specific quest item and not subject to ransack.
On two separate occasions, once by myself by accident and a friend deliberately found that confirmation box did not appear upon clicking the Re-Roll button.
It was the first time I had accidentally done so, and was kicking myself for doing so but more angry at yet another simple UI thing is broken.
Editted OP with amusing reroll bug.
Just for posterity.
I don't know if it applies only to ransack, but it may also apply to empty chests.
I joined a Heroic Elite Servants really late once, and rerolled on an empty chest because I wanted a chance at the Slinger. It took my shards and came up empty.
Bug report got me nowhere.
LOL! Yeah, right! Every time I have re-rolled loot, it has incremented the counter. I have run epic Bargain of Blood so many times and re-rolled a number of times trying to get the Seal of the Midnight Greetings and, when you re-roll, you can make half as many runs before reaching ransack as you normally can. Furthermore, if re-rolling did not count toward ransack, then why do people get the message they have stripped the chest of everything of value on a re-roll when there were contents in there before the re-roll? If it did not count (as you claim), then you could not go from having loot in the chest to having no loot in the chest on a re-roll.