Googlebot Not Rendering Css And Other Resources

I am having trouble with Googlebot fetching and render css and other resources without "temporarily unreachable" error and won't render the page. I don't have this issue with other CS-Cart sites. The obvious concern is the potential impact on ranking. Pages render fine in browsers for end-users.
CS-Cart v 4.3.9, Dedicated Linux server, Apache 2.4.18, EasyApache 3, PHP 7.0.22, MySQL 5.5.55-cll
Googlebot couldn't get all resources for this page. Here's a partial list:
URL Type Reason Severity Style Sheet Temporarily unreachable -- Script Temporarily unreachable -- Image Temporarily unreachable -- Image Temporarily unreachable -- Image Temporarily unreachable --
Normally, I check the robots.txt for issues. I am using the default CS-Cart robots.txt
User-agent: *
Disallow: /app/
Disallow: /store_closed.html
Next, I check to see if my server having issues with serving up the pages? Page speed helps me look for bottlenecks. But the page seems to load quickly. No 503 errors on server or other discernable issues with serving pages. Server error logs look clean.!/bsrXSy/
The index page loads in 2.16s, performance grade B 87
page size is 679.5 kb