I think someone brought this up before in another thread...
Page 216:
In the first days of the Siege, the CS launched a preemptive nuclear strike on the Twin Cities (Tolkeen and Freehold),
only to watch the ley lines surrounding the cities energize and swallow up the nukes before they could reach their target.
(Incidentally, nukes are forbidden by standard Coalition mission doctrine. Their use against Tolkeen was an unwarranted deviation
from that policy, and the officers responsible for the attack were executed for their transgression.)
When the "Hard Rain" bombardment commences, it uses non-nuclear warheads
(although the term "nuked" is still used to describe the destruction).
Later, many will insist that the CS used limited tactical nuclear missiles,
but it is not true and they did not need them.
Page 218 gives an example scenario where merely launching 8 long-range nuclear missiles is something an 'insane' Lieutenant plans to do this without authorization (he is merely an artillery commander and is substituting nukes for other less damaging armaments) and risks destroying have of Minnesota.
Page 22 says under "Other Places of Battle 6." does say that CS High Command is considering "limited use of tactical nukes". This doesn't actually conflict with page 216 though: High Command is considering them against Freehold but has not used tactical nukes so far, and hasn't needed to use them so far.
Page 102 mentions there was a "Coalition attempt" to launch "short-range tactical nuclear missiles" against Freehold but that they exploded and destroyed the mobile base before launch.
Regarding the range I think that would mean they were using medium or heavy (1000 miles) instead of the highest-damage multi-warhead (1800 mile) types.
So as best I can tell...
1) per 22 the CS High Command is considering limited tac-nukes
2) per 102 someone in the Coalition was attempting to launch one but got stopped (perhaps the guy on page 218?)
3) per 216 the CS has not actually used tactical nuclear missiles (albeit because an element tried and was stopped before they could be used)
I think I found a couple places that what you're talking about re the ancient dragon descriptions though.
Page 144 describes the Dragon King (I think all DKs are Ancients) named Rexus (Fire) and this:
It doesn't matter that they will claim tens of thousands of Coalition soldiers and lose the city only when half of it is bombarded with tactical nuclear missiles!
This doesn't sound like it's happened, more like it's discussing a hypothetical scenario for the only way the Dragon Kinds could lose the city. This links back to the discussion on page 22 which says they want to destroy half the city with tactical nuclear missiles.
Given that Freehold DID fall though, I guess we could assume this is what eventually happened? The next quote seems to support that...
Page 153 describes the Dragon Prince (I think just Adult, not Ancient) named Xevek (Zaayr Crystal) and this:
As fate would have it, the noble dragon escapes decimation from a volley of nuclear missiles that lays waste to half the city because he is away taking several hundred people to a ley line in Wisconsin.
So that seems to support, at bare minimum, that a volley of two LRMs (doing at least 2 x 2D6x10 MD using old-style damage, higher if using the higher-damage ones introduced in CWC, both models exist) are destined to hit the city.
The thing about 153 though is it is a continuation of 152 which says "Siege Notes: If there are heroes among the dragons who stay to fight for Freehold," meaning the entire thing is only a hypothetical scenario. The CS using tactical nukes is introduced as a possibility, not a guaranteed outcome. If the dragons fled then there wouldn't be reason to pollute the environment and waste precious missiles bombing the city with nukes.
Is it possible Aftermath might have information confirming whether or not nuclear missiles were used?