Learn Farsi: به دلیل خشونت، مقرر می‌شود که داور او را جریمه‌ی نقدی کند. - Due to violence, it is stipulated that the referee issues him a monetary fine.

The phrase مقرر می‌شود (it is stipulated) introduces a formal rule or decision about an action that needs to happen. This requires the subjunctive mood. The conjunction که (that) connects the stipulation to the action itself, forcing the verb of that action into the present subjunctive: کند (from کردن).

How exactly does the phrase جریمه‌ی نقدی کند translate, and why isn't the word جریمه enough?

جریمه alone just means "penalty" or "fine," which in sports could mean a yellow card or a point deduction. Adding the adjective نقدی (cash/monetary) specifically makes it a financial penalty. Combined with کند (the subjunctive of کردن), it forms the compound verb "issues a monetary fine."

Why is the direct object او را placed before the word جریمه‌ی rather than right before the verb کند?

In Farsi, specific direct objects marked by را usually come before the non-verbal noun of a compound verb. Here, جریمه‌ی نقدی کردن (to fine monetarily) is the full compound verb, so the object او را (him) must sit right before جریمه, rather than breaking up the noun and the auxiliary verb at the end.

Do I need to pronounce an ezafe between دلیل and خشونت?