We know that there haven't been quite as many Treasure Hunter Mole Miners around as we're all used to seeing during these events, due to a bug affecting enemy spawns. We're actively working to fix that issue as soon as possible, and once we do, we're going to hold another Treasure Hunter weekend to help make things right.
The fix is still in testing, so I can't promise a date just yet, but we're now aiming to roll it out sooner than the patch that's coming later this month. If that changes, or if I hear any updated information on timing, then I will let you know!
As far as Ornate Treasure Hunter Pails go, we haven't adjusted their drop rates. But since there's a smaller chance for Ornate Pails to drop vs. the others, it is possible to run into some bad luck. I'll bring up your reports with the team though, so we can double check that there isn't anything unintended going on with them.