How To Start A Branded Tier 1 Syndication Network If You Don’t Have Access To The Main Site To Create RSS?

In episode 249 of our weekly Hump Day Hangouts, one participant asked how to start a branded tier 1 syndication network if you don't have access to the main site to create RSS.
The exact question was:
Hi guys, I created a branded tier 1 syndication network for a friend who has a local business (beauty niche) and I want to start publishing to it but I don't have access to the main site site yet to create an rss feed. What would be the most effective way use to start the process. Blogger? Worpress?. (free) I was also thinking of using the rss feed form the GMB briefcase.
