Ubisoft has changed the solo thunt renown gain which is now based on time.
I don´t know if this still works in online mode but i´m too lazy to find out.
R.I.P

Today i have found out how to bypass this "nerf" , there are 2 ways the easy way is to get a second player that you do this with and then you follow the same steps. The second way is to have the matchmaking preferences set to those in the guide and hope that you can find a thunt match that is set on house, afterwards you need to restart that match atleast once. After that you can wait for everybody to leave and you will be able to replay the thunt match of extract hostage with the un nerfed amount of renown.

When the Flare is there the hostage spawns here:

After you kill the enemies inside of there you will have to take the hostage and escape as follows:

If the Flare spawns here:

That means the Hostage spawns here:

The escape route goes like this:

If you do not see the flare at The Truck or The Docks that means the Flare spawned by the construction site, which means that the Hostage spawned in either place:


Once you get the hostage you will have to escape this way in order not to die:
(Spawn 2)

(Spawn 1)

If you are legally blind then you can see that the ammo box always spawns near the hostage, the ammo box looks like this:

EDIT:
1.As noted by ✪ SaiKo if you repell up the garage door you can see the ammo box which makes it easier to see the hostage.
2.Sometimes you don´t get the renown that´s because there is a "time limit" which means you will have to let the timer go down one minute to actually get the renown.
That´s it.
Once you do this enough times you will end up a rich lad.