Артур не изменил бы своего решения,

Артур не изменил бы своего решения, даже если бы Джемма попросила его об этом.

Results (English) 1:

Arthur wouldn't change its decision, even if Gemma had asked him about it.

Results (English) 2:

Arthur would not change its decision, even if Gemma asked him about it.

Results (English) 3:

Arthur has not changed its decision, even if the Gemma asked him about it.