Ummm...

Check if cache files are actually removed in <magento-directory>/var/cache/. If not then you can manually remove them.</magento-directory>

Sorry to heard that.

I don't know your technical skills and this would probably sound silly, but did you refresh your browser cache?

Hi Kevin,

Did you try to refresh Magento cache? Go to System > Cache Management

Hope it helps

In order to put those image URLs for the crawler to be able to access them you should either:

• Link to the URLs of the images (does that .html page in the subdomain contain these URLs?)

or

• Use the images URLs as resources in the pages already been crawled. Unfortunately this could be tricky when dealing with CDNs since those resources are dynamic.

In either case, the sitemap will solve your problem.

Did you reference the sitemap in the robots.txt file or did you set up it in GWT?

Yes, you have to create a property for every subdomain since every subdomain has different peculiarities, like the instructions in robots.txt

You may also want to reconsider to put your blog in a subfolder instead a subdomain. This has been the recommedation from Moz for a long time and still is. You can find the explanation here: https://moz.com/blog/subdomains-vs-subfolders-rel-canonical-vs-301-how-to-structure-links-optimally-for-seo-whiteboard-friday