Malgat explained he needed some time to complete a gift for you. He asked to wait for some time and then return to him for your reward.
'You inspire me, ${PLAYER}. I shall begin my work on a reward suitable for the efforts you undertook for me and all Jirush. Please return to me when you are able. It will take me only a short while to do what I must. I promise the reward is worth the wait.'
Malgat offered to provide you a gift. You only need wait a little while for him to finish his work. Adventure elsewhere for a few minutes and then return to him in Jirush.
Enough time has passed. Malgat is likely done with the work on your gift. Make your way to his location in Jirush to claim your gift.