TO vs SO THAT

which would one say

1 He got close to a man he said was his son, a son he did not know he had, to ask him for a kidney as he was dying and his only chance of survival was if his son would be kind enough to be that donor

2 He got close to a man he said was his son, a son he didn't know he had, so that he could ask him for a kidney...

1She left a note on the fridge to not forget to water the plants /so she wouldn't forget to water than plants

one more thing

which is correct

How many more points do you get when you hit a strike than a spare?/How many more points do you get when you hit a strike rather than a spare?

thank you