307 head gasket and water pump damage

Can a leaking head gasket cause damage to the water pump? Cause this is
the story I heard today from the service manager of my local dealership.

FYI, the car had started producing a distinct engine noise at 65K
(kilometers, not miles), which the mechanics attributed to a water pump
going bad. They replaced the pump and timing belt while at it.

But is their theory plausible? Also, I know about the oil in coolant and
coolant in oil symptoms when a head gasket blows. But can the leak be
actually visible, such as a valve cover gasket one?

Thanks,

Nikolas

ps. Peugeot 307 1.4L petrol, 2003, 65K.