Original sentence: Lord Shiva replied that he had granted Ravana the boon of indestructibility
Edited sentence: But ravana was jaya who is guarding the entrance of lord vishnu's residence and cursed by four sons of brahma and his destiny lies in the hands of lord vishnu).In this version of Ravana's story, his battle with Rama can be interpreted as a pretext to attain death, and through death, liberation.Lord Shiva replied that he had granted Ravana the boon of indestructibility, and that Ravana must instead seek moksha from Lord Vishnu(According to srimadbhagavatam  chapter6 verses 43 to 50 it is clear that Shiva is ordaining jivas to spiritual world and heavens etc.So Lord Shiva can give liberation to any one