That doesn't comply with code. From the 2021 IRC:
E3608.1.1 is a metal underground water pipe,
E3608.1.2 is a concrete-encased electrode,
E3608.1.3 is a ground ring,
E3608.1.4 is rod and pipe electrodes,
E3608.1.5 is a plate electrode, and
E3608.1.6 is any other grounding electrode.
If an existing connection to a CEE is cut (disconnected), that's a violation. Unless they cut the wire leading to the CEE flush with the face of the concrete, it should be possible (and required) to repair the connection, not abandon it.
IRC E3608.1. The CEE is present, therefore any other grounding electrodes you add must be bonded to the CEE.