Jesus could not go to Purgatory, let alone hell. There was no sin in him, no culpability- had he tried they would have become paradise, and all the sinful fled away in the face of his brillliant purity.
But he could suffer on earth. And suffer he did. Why not just send a prophet to suffer? Many of God's prophets had suffered for Him in the past- why did God have to do it Himself. Two reasons: 1) God loved us too much to make any of us go through that much pain and despair, and 2) Only one who was 100% God as well as 100% man could have had such perfect control of the body, forcing the mind to consciousness, the legs to walk to Golgotha- as it has been said "Nails could not have kept Jesus to the cross, had not love held him there". A simple, mortal man would have died at the pillar.
Despair, though, I hear you say! How could God despair, how could his suffering have any value if he knew he was God, knew it was temporary. That's not what it's like to be human, that's not our suffering! What does God know?
That is why, at the height of His pain, naked before the vituperous crowd, His ruined back scraping against the wood as He pushed with shattered feet against the nails for one more breath, his mother's weeping filling His ears, God turned His back on God, and Christ was alone, with the guilt of the sins of a trillion people, from Mengele on down to your own eight year-old self kicking the next-door's cat pouring down on his very inmost being.
And at ninth hour Jesus cried out in a loud voice, "Eloi, Eloi, lama sabachthani?"--which means, "My God, my God, why have you forsaken me?"
And died, in perfect faith.