To put it simply, I duped the child trade item slot into a bottle, equipped it as an adult (with a stuffed inventory), and went and got the weird egg from Malon, since this was a file in which I had not actually gone to see Zelda. I waited for the cucco egg to hatch, became an adult, and used death hole wrong warp to get to Hyrule Castle as an adult. Then I just used the cucco to wake Talon.