Seriously, like I stated above..... put aside those White Hots.
Sounds like everyone's been shooting out of the same box of White Hots - taken the entire box on multiple trips to the range and now they're moisture-contaminated.
But instead of buying more White Hot pellets, buy a better powder to use, like Blackhorn 209. If the family wants to continue their success with White Hots pellets, let them buy their own.
I'll bet that new Optima V2 will love Blackhorn 209 and shoot that powder/bullet combo accurately.