"correct" (most widely used) solution here is:
Es ist kaputt wegen *dir*.(which is dative)
Es ist *deinetwegen* kaputt.(which uses an adverb)
correct genitive were: deiner
Es ist kaputt wegen *deiner*
"wegen deiner" mostly gets replaced by the adverb "deinetwegen" in spoken language, if there is not some object deiner can refer to.
If some object is given native speakers mostly use:
Es ist kaputt wegen *deines Fehlers*.
It is broken because of your error.(or whateverm might have happened)
You ran into a currently changing construction there.
citing from the linked question: (bolding by me)
Sie ["authentic" pronouns like "wegen"] können nur mit dem Dativ oder dem Akkusativ stehen und grundsätzlich nicht mit dem Genitiv.
and again citing from linked question:
Anzahl von Präpositionen, die mit Genetiv verwendet werden. Darunter auch wegen.
Your example is awkwardly chosen. As visible in the canoo.net article there in fact are constructions with genitive, but almost noone uses the really correct way in speech, because it seemingly sounds "awkward"...