I've completed the Breen arc mission
Cold Call and got a Cryo Grenade (this one:
https://sto.fandom.com/wiki/Cryo_Grenade). Now, I know there is the Biothermal Dampener as a permanent device, but that one isn't useful in combat.
I've read on the wiki that, once a player runs out of these Cryo Grenades, assistant manager Vux on Defera has 'a 50% chance to offer them every hour'. I've checked in at least six different hours since yesterday, during three hours I was actually out of grenades. I've yet to see anything else than Snowtubers being offered by him.
My questions are as follows:
1. Is it actually true that Vux sells these Cryo Grenades?
2. Is it actually required to have no remaining grenades, before you can buy new ones?