Usopp was extremely stressed and depressed too.He made a mistake and was eventually confronted and made to apologize for that.Why doesn't that apply to Sanji too?
1. He is not Usopp
2. Completely different situations and standards. The first Younko territory presented as "extremely dangerous" and as a place from where no one could escape without permission can't be compared to mere Water 7.
3. Luffy himself acknowledge the tough situation Sanji was probably going through, all of the decisions he took, smart or not, were all due to his admiration and hopes for Sanji. Blaming Sanji for his decisions but completely ignoring the consequence of Luffy's decisions doesn't seem fair or smart to me
4. Sanji never judged Usopp or tried to blame him for his actions, he never did that to Vivi, Robin or Nami (these are the character people bring up to compare to Sanji), he was simply there to help them overcome the troubles they were in, despite their decision making and the actual situation.
5. Sanji didn't do that on purpose or due to potentially selfish actions, it's the opposite, he did that aiming a greater good, to protect those he cared about the most given all the info he had at that moment. If you read all through WCI and think Sanji needs to beg for sorry, and even bring Zoro to the matter like he had anything to do with this, then yeah it think its impossible to change your mind