I'm pretty sure that statute of limitations laws don't govern civil suits (just as double jeopardy laws don't apply to wrongful death suits).
1) Yes they do - that's their purpose
2) Double Jeopardy applies to criminal cases
3) Wrongful death suits are civil suits
4) The SOL in this case depends on state law.
"Title IX, like many federal statutes, does not have its own statute of limitations. Title IX claims are thus governed by the most analogous state-law statute of limitations, typically the one for personal injury claims."
https://verdict.justia.com/2011/11/15/the-penn-state-scandal-why-is-no-one-talking-about-title-ix-2