i'm sure the other solutions work ok but save yourself some hassle and just get some of these
NP :) Let me know what you end up going with.
Here is one thing that you should really consider. Cigar's are very sensitive to humidity. That's why(as I'm sure your aware) cigar's are stored in humidors, where the humidity is controlled, and held at a very precise level. Since you don't have a humidor, I would highly recommend one of the following two options:
1) Give the cigars to your brother a two or three weeks before the bachelor party. Obviously tell him that your intention is to smoke them together. Then he will be able to place them in his humidor for safe keeping.
2) Use a zip-lock bag and a boveda pack. A boveda pack releases and absorbs moisture to maintain an exact level of humidity in a confined space. A zip-lock bag is a cheap, airtight container that will allow you to store the cigars with the boveda pack. Put in a drawer(somewhere away from direct sunlight.
I would get this: https://smile.amazon.com/dp/B00FWPQ9D0/ref=cm_sw_r_cp_apa_fabc_5G34RKZHHPV802EFKHFP
You could probably get away with a small one but with boveda you can't over humidify so too big is better than too small in this case.
Rehydrating dry cigars takes a bit of time so I'd go slowly. The jar is fine. It will work perfectly. Just replace the stick humidifier with a Boveda pack because it works better and is maintenance free: https://www.amazon.com/Boveda-69-Percentage-Individually-Wrapped-Humidity/dp/B00FWPQ9D0/ref=sr_1_10?crid=3ALO1C8NNN1C6&dchild=1&keywords=boveda+69&qid=1600362824&sprefix=boveda+%2Caps%2C148&sr=8-10