In the theme – the lat & long coordinates are custom fields. If you have that for each property – you don’t need to click the button to have the address on map.
So – I guess that if you can get that in the xml – that would save you time as once you set lat and long, the address saves on map automatically.
If your xml doesn’t have these fields – you need to create the conversion script from address to lat and long coordinates – but can’t help more here as it’s related to your third part xml and wp-all import. Perhaps someone from WP ALL import can guide you to the right person who has experience in this field.