I think you are correct and that is indeed a pollen sack. I have seen people have success in plucking them away every day. The key is to keep up on them and do not then get to a point in opening up. Sometimes there can only be a handful and it’s easy to remove. Other times it’s just too many and you cannot get them all.
It does look like this sack has opened up as well, which could have pollinated your whole tent. There is always a chance there was no pollen in that sack so hopefully that is the case.
I would inspect that sack to see if you can find pollen left inside of it. If you do, likely the whole tent will be seeded. Unfortunately pollen from a hermi plant is likely to produce offspring that have the tendency to herm more frequently.
I hope this helps.