Well, they kind of have alittle bit already. They used of the name for the smooth headed Klingons in Blood Will Tell, the Myriad Universe title for The Last Generation, and the New Frontier comic.
True, but they're also free to go in a different direction.
Blood Will Tell depicted the history of smooth & ridged Klingons' relations in a way that differs from the way novels such as
Forged in Fire have depicted it -- and the name
quch'Ha used in both works came from the Klingon Language Institute, so it wasn't a case of one work borrowing from the other. And there are aspects of D.C. Fontana's
The Enterprise Experiment that are inconsistent with what earlier novels have established about the "Enterprise Incident" Romulan Commander, the Organians, the Preservers, etc. (It definitely disagrees with what
The Buried Age asserted about Organians.)
See, this is the point I keep trying to get across. There's no absolute, uniform policy either way. Pocket and IDW are not required to be consistent with each other, but they're not forbidden to be either. It's decided on a case-by-case basis, depending on what's best for each particular work, or on the preferences of individual creators and editors.
And just to clarify in response to what
JTK2099 has wrongly inferred: It's not a question of what one publisher "thinks of" the other's work. Pocket and IDW are doing the same kind of work, and there's no rivalry or hostility between them. It's just most practical and desirable for each publisher to have the freedom to make its own independent decisions, since they are separate entities with different editorial staffs, different publishing schedules, different storytelling approaches, and different (if overlapping) audiences. The two get along well enough that crossovers and homages can and do happen, but it's simply a matter of choice rather than obligation.