You proven my point that language doesn't matter. A hund is a dog not a cat. No matter what language you use, that animal is still a dog.
Right, so that animal is still a dog, by which I assume you mean a hund is a 'dog'. One word is a translation of the other...
... and Tolkien, as the translator of The Lord of the Rings, has the word Orc in the original (although his original is Westron not German of course), and he translates Orc with 'goblin'.
Tolkien's love for language doesn't have anything to do with this topic so it's pointless using it to answer the question of orcs and hobbits.
Tolkien ultimately preferred (at least usually) the sound and suitability of Orc rather than 'goblin', because Tolkien the philologist was very aware of his linguistic taste regarding sound and sense. He writes:
Orc This is supposed to be the Common Speech name of these creatures at that time; it should therefore according to the system be translated to English, or the language of translation. It was translated 'goblin' in The Hobbit, except in one place; but this word, and other words of similar sense in other European languages (as far as I know), are not really suitable. The orc in The Lord of the Rings and The Silmarillion, though of course partly made out of traditional features, is not really comparable in supposed origin, functions, and relation to the Elves. In any case orc seemed to me, and seems, in sound a good name for these creatures. It should be retained.'
JRRT Guide to the Names in The Lord of the Rings
This explanation was written to aid other translators of The Lord of the Rings, translating the English version into Swedish or German or whatever.
But since you mentioned Tolkien, he translated the Hobbit and LOTR into English, then both orcs and goblins should've been used as the name of the same race or different race in the 2 books.
And both words were used of the same beings in both books. Or at least, that's the ultimate decision from JRRT from about 1966 forward.
Note what JRRT is saying in my quote above: Orc should be translated to English 'goblin' according to the system -- but at the end Tolkien asks that translators not translate the word Orc, despite his own system.
Why? because he finds Orc generally more suitable and likes the sound.
Essentially Tolkien is telling other translators that technically it should always (or at least mostly) be 'dog' (goblin) like it was in his first book (mostly, as Orc occurs twice outside of Orcrist). But for his second book he asks that translators leave hund (Orc) where it is found in the text -- in other words, do not translate it: retain Orc.
'Dog' occurs now and then, but leave hund in any case.
To continue the comparison of course.