Gigadrain bug vs sturdy?

Hello,

I am starting to strongly believe that there is a bug in the coding of gigadrain. I have been using an oddish with gigadrain to figh geodudes (trying to find a sturdy one) and I have killed all of them (used the move around 50+ times already). I know not all geodudes have sturdy ability but I don't think I can be that unlucky to run into 50+ geodudes without sturdy ability one after the other. I know how sturdy ability works and yes, I am killing them with a single Gigadrain when geodudes are full HP so if they are really sturdy they should hold it.

Few hours earlier I was using Megadrain and it was not single shotting geodudes so it appears to be only about gigadrain.

I hope that if there is some issue here it can be solved. I will report if I would notice some change but it has already been too many geodudes to think it's just a luck thing.

Thank you,

GruntGG