Why doesn’t the titan fall where I point

The epilogue of the fight really only matters for the losing team to gain a consolation prize. Where-as for the winning team, it's similar to the Team Fortress 2 humiliation period at the end of a round.

During the Epilogue, the evacuating team have an attempt to earn an additional Merit (EXP for Titanfall 2) if they manage to make it back onto the drop-ship and survive the encounter. Everyone at this point cannot respawn anymore, so any attempt to pick off the "victors" of the match will help improve the chances of a successful evacuation. (ie, If the enemy team has less high powered weapons, they'll very likely be unable to destory the drop-ship.)

On the other side though, it does not seem the winning team has much else to gain from preventing the evacuating team from escaping. From experience, it seems that kills during this round will still count towards one's progression, but I have not noticed any merit points for a team kill or drop-ship destruction.

If you have enough of your core bar charged, you can use the counter rodeo measures, which deploys your electric smoke. This won't stop the pilot outright, but if you react quickly enough, it typically can get them down to 10% HP.

If you're near allies, they can shoot off the pilot and a friendly titan can just melee them to insta-kill them. Granted, the best thing to do is not get rodeo'd at all.

To do that, try to avoid high buildings/walls, as pilots need to attack from above to rodeo. If they drop down, it's much harder to spot them. If you do spot a pilot trying to get on you, a titan melee can one-shot them and titan guns can usually 1 - 2 shot pilots, with the exception of legion.