While turning down temperature might help as it will be less fluid, i tend to think that increasing retraction might give him other problems (unless is settings are really low). On pictures we only see stringing at the top where printing areas are very small which means much more retraction are needed. His issue could be related to maximum retraction count and/or minimum extrusion distance, when those numbers are reached, printer will not retract filament to protect grinding too much filament. Others parameters to look out are retraction speed and prime speed but since OP didn’t share settings, no way to tell what he could try.
Looks to me like your temperature is too high and you need to increase your retraction distance.
Also may help to have improved blower (fan replacement/more focused outlet)
While turning down temperature might help as it will be less fluid, i tend to think that increasing retraction might give him other problems (unless is settings are really low). On pictures we only see stringing at the top where printing areas are very small which means much more retraction are needed. His issue could be related to maximum retraction count and/or minimum extrusion distance, when those numbers are reached, printer will not retract filament to protect grinding too much filament. Others parameters to look out are retraction speed and prime speed but since OP didn’t share settings, no way to tell what he could try.
To OP, please share your printing settings.