Acquire or develop talent
I would recommend Tanglewood to develop talent. In the case, they stated they hired people with managerial skills, but didn't hire them as managers. Tanglewood has a specific culture that isn't easily acquired. They prefer promoting within so they are familiar with the culture. If they develop talent from their recruiting, the newly recruited people will have a better understanding of the company and work ethics will reflect the culture.
Hire yourself of Outsource
Tanglewood should do the hiring themselves. Again, they have such a specific culture and way of doing things that it only makes sense for them to select who to hire. By outsourcing, they are giving someone else the power to hire and they may not know exactly what Tanglewood is looking for.
External or Internal Hiring
I would suggest hiring internally for higher positions. When Tanglewood hires a new employee with management potential, they still spend a period of time as a sales associate to understand the company. It's important for Tanglewood to trust their employees to do things their way. By hiring internally, Tanglewood will know who has the right potential to be promoted.