I would say yes. I've done the charity route in the past when I really didn't want to miss out on specific races. The bonus is that going the charity route is usually less stressful, as many charities can guarantee a bib before general registration. It feels good to not have that registration stress

The list of different charities is available here:
https://www.rundisney.com/plan-your...viders/disney-princess-half-marathon-weekend/
You could reach out to the charities that speak to you ahead of July 30th to see if they have bibs for you and your husband.
As for the DVC question, I'll let others more knowledgeable answer. I'm not an owner or a renter.
All WDW resorts are great for race weekends and have their own pros and cons. It's more a matter of personal preference.