Lillian Morgan (the original) has the following trait:
When Lillian enters a posse, place 3 ghost rock on her. The ghost rock may be used to pay for Shootout abilities (it is not a bounty). Discard her unused ghost rock after the shootout.
It's clear that it can be used for abilities like her own, where the text is in the form "Shootout, Pay X Ghost Rock". But can she be used to pay for things described in the text of a Shootout ability, such as Raising Hell:
Shootout Hex 8, Boot: Ace a card from your play hand. One Abomination from your Boot Hill enters play (pay all costs) and joins this Huckster's posse. Ace this card.
Shootout: Play a dude from your hand into your posse, reducing their cost by 5. When the shootout ends, pay 3 ghost rock or discard that dude.
Or An Accidental Reunion?
Shootout: Each time a player reveals an illegal draw hand, that player takes two extra casualties that round. You may pay 2 ghost rock to place this card back into your hand.