In reading your Sky Ocean article, I want to note a few things that aren't simple typos, and may warrant discussion:
1. I am not a physicist, but I am dubious of the traditional disproof of the water canopy that "all that water would have crushed everything". The weight the water would impose on our atmosphere would surely depend on how far it was from Earth's center. If the water were high enough, it wouldn't weigh anything at all (it would also be frozen, but I don't think that is problematic since the Bible doesn't say it wasn't).
2. If the water canopy affected radiocarbon dating, we would not expect to see an "offset" or gap in the ages of objects. Rather we would see a change in the rate of frequency of different ages found through this dating method because the rate of radiation entering the atmosphere had changed. Only a sudden, massive spike in radiation would cause a gap in the ages found.
Thus objects would still be found that dated to right before the Flood, but pre-Flood ages would stretch out in time, having wider spaces in-between them, because they actually represented a smaller range of time than thought, like 2,000 years, being assigned to a range of 200,000 years -- if in fact the pre-Flood objects were being overestimated in their age by scientists. However...
3. Offset or no offset, I believe that the water canopy excuse actually hurts the case of creationists rather than helping it. If there was less radiation before the Flood because of all that water absorbing the rays from space, then that means C14 would decay more slowly. That means that an object that we think is X years old would actually be, say, 10X years old because we were severely underestimating how long an object would have to be exposed to atmospheric radiation in order for the C14 to decay that far. So C14-dated objects would actually be far older than scientists thought.
The Society has written their statements in what seems like a deliberately vague way, such as "any change in radiation would have altered the rate of formation of radioactive carbon-14 to such an extent as to invalidate all radiocarbon dates prior to the Flood", rather than stating which way the dating would be swung, because somehow C14 would have to be decaying faster pre-Flood in order to support a creationist timeline, and I think they are aware of that.