No. The requirement for getting out-of-scope for the non-CDE enviroment is that its totally isolated in such a way that the non-CDE enviroment - if totally compromised, this should read as "totally taken over and owned by the attackers" - should not be able to compromise the CDE enviroment - not even reduce the security the smallest bit. (CDE enviroment = "PCI Zone" in your question)
The security risk you expose the CDE enviroment for by exposing a read-only fileserver to the CDE Enviroment that is writeable from the non-CDE enviroment is that the server can be infected with a virus that originates from the non-CDE enviroment, that a PCI user might access and cause havoc inside the CDE Enviroment.
A better way to accomplish this transfer of information, is to transfer the information in such a way that it can never be interpreted as executeable files. Think a one-way RS-232-channel from non-CDE to CDE, that is handled very restrictive in the CDE enviroment. Best way to accomplish this is to use a RS-232 to optical fiber at the non-CDE end, and then a optical fiber to RS-232 at the CDE end, and then you only connect the transmit port on non-CDE to the receive port on the CDE side.
You must ensure that regardless whatever is put into the non-CDE end of the RS-232 channel, the CDE enviroment may not be affected security-wise.
This means you need to configure the RS-232 receiver in such a way so the charset is limited so even if a user copies a file off the server that handles the RS-232 receiver and for example, Changes the file extension from .txt to .exe, the system must stay safe. This means very restrictive settings on the RS-232 receiver.