According to the rules cited in my other answer to your question regarding Dedicated Transports, you are permitted to attach either a Librarian or Reclusiarch (either in Terminator Armour) along with your Death Company and deploy them in a drop pod because these models are also independent characters.
There is an additional stipulation, however, which is that Terminator Armour, by virtue of being enormous, counts as two models, reducing your Death Company capacity to 8 + your HQ.
In the codex, p. 61:
Terminators count as two models for the purposes of transport capacity
There is an unfortunate ambiguity of the Rule-as-Written interpretation by writing "terminators" rather than "a model wearing Terminator Armour", as the rest of the paragraph uses. But for Rule-as-Intended, I believe it is clear that by virtue of being placed under ARMOUR (rather than the Terminator entry)--and by the fact that Terminator Armor is still huge (whether worn by a normal squad or by a Librarian)--that the intended rule is "any model wearing terminator armor counts as two models for the purposes of transport capacity".