There are 3 correct ways to recognize your wife's participation in your business activities.
A. Treat her as a partner. If you are not an LLC, this is a "qualified joint venture". You divide the income and expenses between 2 schedule Cs based on your relative participation in the business. She can deduct her expenses as usual. (If you have an LLC, this gets a little more complicated.)
B. Hire her as a W-2 employee. You can then reimburse her expenses under an accountable plan.
C. Hire her as a subcontractor. Your payments to her are a business expense to you and gross income to her on a schedule C. She can deduct her ordinary and necessary expenses.
Note that, by including your spouse in your business, your spouse builds credits with the social security administration for retirement or in case of disability.
Now, as to your specific question, can you pay for a person who is not a contractor, employee or partner to undertake business activities on your behalf? Probably. You need to be able to make the case that these are ordinary and necessary expenses for your business.
But note that travel, meals and lodging are subject to certain rules as described in publication 463, chapter 1.
https://www.irs.gov/forms-pubs/about-publication-463
