by kkstiles
It took us a while to get it straight in our heads too. We eventually landed on what you said (except I think you meant unsuccessful in the first bullet).That's a good idea to compare Contamination stickers to Surveillance stickers, both added at end of game, the former due to Outbreak side of "barrel", the latter due to Incident side of "barrel".
Regarding the downside/risk bullet, doesn't running out of green cubes also end the game? So that would be another downside/risk of cubes spreading beyond Exposed cities.