Can the PZM-11LLWR be changed from its line-level output to a mic-level output?

Yes. In the PZM-11LLWR circuit board, change R5 to 180K or 190K. This should get the PZM11LLWR back to a mic level output.

Please see the drawing below, which shows the component map of the PC board. The R5 chip resistor (1k ohms) is in yellow.