My balance owing is the same amount as my spouses credit. Is there a way for his credit to pay my balance instead of me having to pay and him getting money back?

Unfortunately not. While you can prepare the returns together they are always treated as separate filings in Canada. You don't have to submit them at the same time. So you could submit your spouses right away, then wait til the final day to submit yours. You may receive your spouses rebate back by then.