All praise be to Allah Alone, and peace and blessings be upon His Messenger, and his family and Companions.
If the situation is as you have mentioned, you do not have to make Ghusl in the first case. Also, in the second case
you do not have to make Ghusl as long as the glans of your penis does not penetrate the vulva. Otherwise, you have to make Ghusl. The ruling for the third case is like that of the second case, but the man must wash his penis and testicles for the discharge of Madhy and the woman has to wash her vagina if she also discharged Madhy.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.