Is it permissible to deal with someone who claims the ability to unblock my husband's account on Careem in exchange for money, especially since my husband might also be blocked from working on Uber, and our debts are accumulating?

Contracting with "Careem" company is an unbinding partnership contract, where the company provides marketing and customers, and the driver provides the car and labor, and they share the income. Either party has the right to terminate the contract at any time, as Ibn Qudamah mentioned in "Al-Mughni".

If the company bans the driver, he is not allowed to use deceptive means to return, because the contract is based on mutual consent. The solution is to communicate with the company to lift the ban, otherwise, he should go to another company, for sustenance is in the hands of Allah.