Didn't she get hurt before JWC and Radinova who was also injured wound up going instead.
No, that was Sotskova who got injured before junior worlds. Proklova did not compete because Radionova was injured and she got better, they decided to give her a chance and compete so they swapped her with Proklova (out of Sakhanovich, Sotskova and Proklova who were at that time nominated to compete, Proklova's result at junior nationals was the lowest and junior nationals was their qualifier for the junior worlds). Then a few days after they swapped Radionova with Proklova, Sotskova got injured and they couldn't get Proklova back on the team any more so they put there Medvedeva. If Sotskova got injured a week earlier, they would have swapped Radionova with Sotskova and Proklova would still compete at junior worlds. That was a bit unlucky.