Regarding orkish, in the appendices of LOTR Tolkien writes that:
It is said that they had no language of their own, but took what they could of other tongues and perverted it to their own liking; yet they made only brutal jargons, scarcely sufficient even for their own needs, unless it were for curses and abuse. _
But Orcs and Trolls spoke as they would, without love of words or things; and their language was actually more degraded and filthy than I have shown it.
But I actually prefer the versions in which Melkor actually took the time to create a language for them:
Orquin, or Orquian, the language of the Orcs, the soldiers and creatures of Morgoth, was partly itself of Valian origin, for it was derived from the Vala Morgoth. But the speech which he taught he perverted wilfully to evil, as he did all things, and the language of the Orcs was hideous and foul and utterly unlike the languages of the Qendi. But Morgoth himself spoke all tongues with power and beauty, when so he wished.
The Orcs had a language of their own, devised for them by the Dark Lord of old, but it was so full of harsh and hideous sounds and vile words that other mouths found it difficult to compass, and few indeed were willing to make the attempt. And these creatures, being filled with all malice and hatred, so that they did not love even their own kind, had soon diversified their barbarous and unwritten speech into as many jargons as there were groups or settlements of Orcs. Thus they were driven to use the language of their enemies even in conversing with other Orcs of different breed or distant dwellings.
Melkor being exposed to and fluent in languages that were beautiful to the ear and still, in his constant state of spite, creating a language that was basically ugly sounds and swearwords is so on brand for him.
And it's so funny that Melkor would sit down (probably thinking of the Valar and all of the long list of people he hated) and create a vocabulary focused on profanities and abuses, making the language he created a poor means to communication and therefore defeating the purpose of creating a language in the first place. So is Tolkien's distaste for the kind of language he had in mind for the Orcs, to the point that he censored it in the text.
