Is the deferred dowry considered a debt that is to be deducted from the estate of the deceased? What is the ruling for the gold jewelry that my husband borrowed from me?

The deferred dowry is considered a debt that a wife is to take from her husband's estate before its division. The remainder is then proportionally divided among the legal heirs.
If it is proved that the husband had borrowed gold jewelry from his wife, then this gold is a debt on the estate which she is to take before its division. Allah the Almighty says,
(The distribution in all cases is) after the payment of legacies and debts. [An-Nisaa`: 11]
The wife must receive the gold in its original weight and not its value at the time it was loaned.

Allah the Almighty knows best.