English to Spanish Art/Literary Poetry & Literature

Good evening everyone!

I have a problem with the use of made up Cockney slang in a novel I'm translating and I'm not so sure of the best way to solve this problem, since there are a couple or three more instances of it throughout the novel.

The thing is, the character uses slang rhymes he has made up (due to inability to use the real Cockney) with another character from a different part of the UK, who, for this reason, is not familiar with Cockney.

I copy an instance here. Thanks so much in advance for having read all this!!

—“I can’t. I’m in turtle, aren’t I?”
“You’re what? In turtle?”
“Yeah. You know, turtle dove.”
“Turtle dove?”
“Turtle dove—love. I’m in love, aren’t I?”
“Fookin’ ‘ell, Max” said Brandon, looking up to the ceiling and shaking his head slowly in disbelief. “You and your bloody Cockney rhyming slang.”
Actually, I had given up using real Cockney slang a while ago (mainly due to the fact that I didn’t know any more than the well worn and topical slang like: apples and pears and plates of meat etc. ) and had started inventing my own. Brandon, being from Birmingham, of course was none the wiser.