In short, ECAM senses damage by the pushed Fire button. Then it asks you to shut the Cross bleed manually. Since Anti ice should be symetrically used it asks you to close it.
That is all provided the first condition is met i.e. "If wing anti-ice ON:" - hence the request to switch "WING ANT ICE .... OFF"
If wing anti-ice is not on - non of that logic is displayed.
If you get a chance, please investigate your simulator ECAM logic with WING ANT ICE OFF, APU Bleed ON & ENG FIRE pb-sw pushed.