Siri female available in voice dream reader

no.

There are a few female iOS voices available.
Catherine,, Karen Martha, Moira, Nicky! Samantha and Tessa.

I like the Voice Dream Sharon. Some of th ios voices are good too.

It looks like the default voice Siri uses is Samantha so yes that Siri voice is available.

If you are looking for the method to access the Siri voices in Voice Dream Reader then here is the path.
Open Voice Dream and down at the bottom you will see a cog symbol. Tap on that and there is an option in blue about the third line down that says Manage Voices. Select that and you get a drop down menu with all the iOS voices of which Samantha is one of them. Select her or whatever voice you want to use. That’s all there is to it.

Samantha voice is not Siri voice, you can go to the system Settings > Accessibility > Spoken Content and note that Siri and Samantha are different voices that can be checked independently.

Siri voices are voices made by Apple with advanced AI technology that became available only in recent years. Other voices like Samantha were developed by other companies and licensed by Apple using the older technology that was available for at least a decade.

Apple doesn't provide Siri voices to apps like Voice Dream Reader because technically they could be misused to impersonate Siri the assistant and collect private information of the unaware user.

However Apple has allowed apps to access private sensitive functions for more than a decade with system of permissions and it can do the same for Siri voices if it wants to. Since few days ago there is a petition to ask Apple to do that, so you may consider to sign it: https://www.change.org/p/apple-apple-please-allow-3rd-party-apps-to-use-siri-voices-for-improved-accessibility