I think whenever unique pre-engineered modules was ever awarded in CG's, descriptions clearly said so. With words such as "unique" and "pre-engineered" specifically..
When its not, then expected modules are just regular. I dont get the confusion, but its probly experience on my part.
Thats why I didnt bother with this one CG, because who need any other heat sinks than sirious ones? Unless lightweight for small ships, there is no reason to use any other than pre-engineered ones, no matter how much more expensive these are compared to other. (not like its hard to obtain mats for it either)