1. RST pin is an open-drain input/output. It indicates the status of VCC relative to the VPF specification.
2. In EC table of DS3232 datasheet, the minimum operating voltage for VCC is 2.3V.
While the threshold for VPF (power fail) is minimum 2.45V.
That means DS3232 is working properly when 2.3V<VCC<2.45V, however RST is already asserted.
In other words RST assertion doesn't stop DS3232 counting.