-The first victim is : 日原泰生 And has the kanji 日 in his nick name which also exists in the stadium: Nippon Life Stadium (日本生命球場)
-The second one is : 藤出頼人 And has the kanji 藤 in his nickname which also exists in the stadium: Fujiidera Stadium (藤井寺球場) -----The third one is : 和田孝平 And has the kanji 和 in his nickname which also exists in the stadium: Heiwadai Stadium (平和台野球場) -----The fourth one is: 古浦郁絵 And has koura spelling in her nickname ( こうら) which also exists in the stadium: Korakuen Stadium (後楽園球場)
-The fifth one is: 川崎陽介 And has the kanji 川崎 in his nickname which also exists in the stadium: Kawasaki Stadium (川崎球場)
-The last one is : 西野澄也 And has the kanji 西 in his nickname which also exists in the stadium: Hankyu Nishinomiya Stadium (阪急西宮球場)

All their names are connected to baseball stadiums , one more thing that all these stadium are : Closed , rebuilded or fixed
We know the cipher but look at this pic



This pic for baseball stadium and how deffensive players stand which are 9 in total And these number detemine there rules in the game So if we clipped the cypher a bit and added it to this pic we will get Something like this

The numbers are matching with som kanjis
So if we take the matched kanjis in the same order and add them together we will get:

サ ア プ レ イ ボ ー ル ダ
saa pureibooruda
Come on , Play ball !!

This is the official sign to start a baseball match.

There are total of 9 people in the church including Kogoro &Co, thats why the killer insisted on Kogoro to come in a total of 4.
The pitcher is number 1 which means the first victim
.
The killer should be "the last man standing", which is the number 9.
As we see in this suspect : 藤出頼人 His first name is 頼人, which has the spelling ライト (raito), which is the number 9 player in baseball.