My theory is that players can get all reward with just 1 candy if they er Lucky enogth.
So list of reward you get by donating fx 1 R-Gacha become useless unless it have properbilities imo.

The way I think donating Work is that the more points of items you donate the longer waiting time will be garantied. Waiting time can if you are Lucky alwasy be longer but newer shorter that garanti.

Example: If you donat 1 R-Gacha you get a minimum waiting time for 50 min, but if you Lucky you can ge waiting of 1:00, 1:30, 2:00, 2:30 and 3:00.
Most likely also even longer waiting times but I have not been Lucky enogth to get them myself. Each waithing time have a basket with rewards and proberbilities of each reward.


With 1* R-Gacha or 1* Pudding or 1* paronamin I got (waithing time normaly 50 mins):

35 times I got: SR Wild3
28 times I got: SR Wild3 + R Wild
25 times I got: 20 candy + SR-wild 3
10 times I got: 15 candy + SR wild1 + paronamin half
8 times I got: pudding half
8 times I got: R-Girl
5 times I got: paronamin half
3 times I got: SR Wild1
2 times I got: 15 candy + R Girl
2 times I got: N-Girl
2 times I got: 20 candy + SR-wild 3 + pudding half
1 times I got: R-Girl + N Girl

I think this drops relates to waiting times longer tha 50 min:

1 times I got: SR-Wild5 + pudding
1 times I got: Peromin half + Peromin (2:00)
1 times I got: 20 candy + R Gacha
1 times I got: 20 candy + Sr-Wild 3 + perona half
1 times I got: SR-Wild5 + Perom
1 times I got: 20 candy + SR-Wild5 + Perom

Total 135 drops of which 6?? is from longer waiting times.

It is posible to get both 15 and 20 candy with 50 min waiting time.
SR-Wild 3 dont come with 15 candy.
Drops that dont give a SR-Wild3 dont give 20 candy.
If you get a R-Wild you alwasy get a SR-Wild3 too.

SR-wild 5 relates to 1:30 waiting times I think.