Well,the premise is the same as Pandora’s box.
And the question is why place temptation if you,the all-knowing one, already know the tempted one will fail the test.
Yes, in fact Ephiasians 1:4-5 indicates that G-d chose believers in Jesus before the foundations of the earth were laid.
But consider that Isaiah 55:8-9 not only indicates that G-d’s thoughts aren't the thoughts of fallen man, that G-d’s thoughts are higher than our thoughts, but Psalms 94:11 indicates that the thoughts of man are futile.
In fact 1 Corinthians 1:19 tells us that G-d frustrates the "wisdom" of the world.
Fallen man must exercise a little faith in order to get some peace of mind about things like the question that you mentioned.