Kind of hard to say without know at least a close amount of sugar. I would let them carbonate stored inside some kind of sturdy box like those plastic storage containers. If they do blow at least the cap and hopefully not but the glass and spilled beer will be contained. If they turn out intact chill one in a doubled bag or something and give it a try.
Since you use two drops in a 22oz bottle there must be a little leeway. I have also read reports of low carbonation or inconsistent carbonation with them so who knows.
I have also read that Coopers drops are more consistent or use @flars method of using Domino Dots sugar cubes.