Forbidden error on urls with sub-directory root

I just launched a new site for a client and am using Redirection to handle the 301’s.

In my client’s old site they had a ton of files named index.html scattered throughout various directories. For example:

domain.com/subdirectory/index.html

However, Google has indexed these pages like this:

domain.com/subdirectory

My client wants to keep the sub-directories in place because a lot of their traffic is driven by image searches and they’d rather not have to do a whole lot of image redirects. They want to keep the old image files in the sub-directories.

We have redirects in place from domain.com/subdirectory to domain.com/new-url-path , but the problem is that when the sub-directory still exists on the server, linking to domain.com/subdirectory causes a “forbidden” error rather than doing the redirect.

When we remove the sub-directory from the server then the redirect works just fine.

Is there a way to keep these old sub-directories in place and have the redirect work as well?

Thanks in advance.

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