Want to merge static-page WP site with WP blog site, is it possible?

I want to merge one WP site (main company site with static pages) with another WP site (company’s blog w/chronological posts). This is how it is now:

https://www.company.com
https://www.companyblog.com

I want to merge both into a single domain, in order to enable implementation of a membership plugin that can (apparently) only protect one single WP installation. And I want to keep each of them entirely intact. The membership plugin is WishList. Due to its limitations, I cannot do this:

https://www.company.com
https://www.company.com/theblog

… nor this:

https://www.company.com
https://www.theblog.company.com

… because either way would require two WP installs.

Meanwhile, I know that if they were both straight blogs then I could export the posts from one and import those into the other to mash them all together. But in this case I want the static pages and hierarchy of the main company site to remain the same, with a link to the blog posts portion of the installation.

I’m not a programmer, so I don’t yet understand domain mapping or even WPMU, or how to test those to see if they would even work.

Also, I’ve looked all over the forums and not found anything definitive, and nothing about mixing static pages with rolling posts in the same WordPress installation.

Is it possible? Could you recommend what you think might be the best approach and/or resources?

Thank you!