If the rack hasn't been designed or tested by the manufacturer to mount a baby seat, it's unlikely that the bike shop or manufacturer will vouch that it's safe to do so. It's notable that the rack doesn't have any associated weight rating. Also, from the pictures it looks like the rack slopes slightly, which wouldn't be ideal. But if you have an REI nearby, you might go try out:
https://www.rei.com/product/123589/t...hild-bike-seat. Also, as suggested above, you might want to look for a front-mounted seat like the ibert, Bobike Mini, Yepp Mini, or Thule Mini RideAlong.