Can't submit forms after enabling SEO rewrite

I have a primary domain (www.example.com) and a secondary blog subdomain (blog.example.com) set up that both share the primary domain's main menu. Blog nodes are only published and affiliated with the blog subdomain. The node links in the main menu are published to All Affiliates so that they are accessible and displayed on both www and the blog.

I am using Domain Source to specify all the main menu node links as belonging to the primary domain, so that when I'm on the blog, all the menu item links have been rewritten to point to the primary domain. This is the expected and desired functionality.

Everything seemed to be working normally until I turned on SEO rewriting. Now across the entire site I am unable to submit forms, add/edit nodes, make admin changes, etc. I viewed the form action on the domain settings admin page before and after enabling SEO rewrite:

Before: form action="/admin/structure/domain/settings" ...
After: form action="http://www.example.com/ttp%3A//www.example.com/admin/structure/domain/se..." ...

I would like to figure out what is writing this invalid absolute path and any tips to point me in the right direction would be much appreciated.

In the mean time, is there a flag in the domain access database tables that I can manually update that would turn SEO rewrite OFF? Or a drush command to change the domain_seo variable? I'm not able to turn it off by submitting the form on the domain settings admin page because all form submissions are broken at this point.

Thanks