Your ex taking on additional debt after separation should be listed in the court documents, but then discounted as a post separation debt and therefore have no effect on the total equity pool.
Make sure your documentation spells this out clearly. Then your ex has the onus of proving the debt was somehow related the marriage to have it included back in.
Keep in mind judges have a lot of discretion in how they manage a property split, and you want to make sure the debt doesn't stay in just because the judge failed to spot it was a post separation debt.
