I'm not sure if im missing something but, in the quests panel, some Ad Astra quests appear as optional, but if you make the second tier rocket without doing said quests, the rocket quest doesn't count it until you beat the "optional"ones.

I think this is an issue with optional quests in FTB Quests (Fabric) Mod.
Looking at the changelogs this could be fixed with version ftb-quests-fabric-1902.4.16-build.235.jar
So maybe updating to the newest version of FTB Quests will fix this issue. Or remove the optional part from the quests since these Quests from Ad Astra are the only one which use this feature.

@ImAK9 what do you think?