Lets take the sentence {tera'vo' Qo'noSvaD taj vIngeH}, and lets assume that by {Qo'noS} I mean the "people of kronos".

When we read it as "from earth (for the benefit of) the people of kronos", then can't it mean too something like:

"I send it from earth, to someone unspecified, but for the benefit of the people of kronos" ?

Why do the people of kronos *have* to be the recipient ?

What you're asking is whether the beneficiary meaning of -vaD can be separated from the indirect object meaning of -vaD. The answer is not by grammar. The Klingon Dictionary describes indirect objects as a subset of beneficiaries. So you have to rely on context to tell you which one is meant, if the difference is important.

SITUATION ONE: An ancient Klingon knife is found in a deceased collector's collection on Earth. The estate donates the knife to Earth's government, and Earth decides to give it back to the people of Kronos as a gesture of goodwill. tera'vo' Qo'noSvaD taj vIngeH I send the knife from Earth to be received by Kronos.

SITUATION TWO: Terrorists have planted a bizarre bomb under the surface of Kronos which will explode if a certain knife is not removed from the surface of Earth. They don't care where the knife ends up; they just don't want it on Earth. I am on Earth and find myself in possession of the knife. tera'vo' Qo'noSvaD taj vIngeH I send the knife from Earth to benefit Kronos.

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SuStel
http://trimboli.name