Happily, Mandy escaped near-certain doom. However, whether her escape will prevent Jessica from becoming drunk with power, only time will tell. After all, we all know what happened to the Iron Masked Marauder...Poor Mandy, Jessica lost her precious Nexus Rod and took it out on her, but luckily the Heaven's Flute stopped a murder from happening. Hopefully Jessica will come to her senses and not get drunk with Palkia's power.
Yes, Heavy Balls would be great to have in Diamond/Pearl/Plantium, but sadly, you can't get them. Giratina will certainly be a tough capture in Platinum, because he's a Ghost and cannot be False Swiped. (Although, I believe that you fight him at a point where you do not have access to that move anyway.) On the good side, I believe that Cynthia completely heals your Pokemon before you fight him. My advice - bring a lot of Dusk Balls, because the Torn World is very dark. However, the key piece of strategy in trying to capture a Legendary is, save the game before trying.Maaaaan, I know how it feels to try to capture a Legendary Pokemon w/o the Master Ball - when I had my character, DJ Pip, from the current game I am playing, Pokemon Pearl, try to capture Palkia, he escaped the Dusk Ball twice and did a nasty number on my Drapion - and I didn't HAVE any sleep moves! I can guess it's a lot harder in the animeverse because they are very powerful. Anyone who has seen The Collector try to capture Lugia knows how tough those guys are. I didn't even think that the Pokemon were suffering.
Let me just say, capturing Giratina in Pokemon Platinum is NOT going to be easy. <_<