Решил проблему.
В файле events.xml заменил children с Land_Wreck_sed01_aban1_police и Land_Wreck_sed01_aban2_police на Land_Wreck_sed01_aban1_police_DE и Land_Wreck_sed01_aban2_police_DE, соответственно.
Убавил lootmax с 5 до 4 и прописал <lifetime>14400</lifetime> и count_in_map="1" в types.xml для Land_Wreck_sed01_aban2_police_DE и Land_Wreck_sed01_aban1_police_DE
<event name="StaticPoliceCar">
<nominal>10</nominal>
<min>0</min>
<max>0</max>
<lifetime>2500</lifetime>
<restock>0</restock>
<saferadius>500</saferadius>
<distanceradius>500</distanceradius>
<cleanupradius>200</cleanupradius>
<secondary>InfectedPoliceHard</secondary>
<flags deletable="1" init_random="0" remove_damaged="0"/>
<position>fixed</position>
<limit>child</limit>
<active>1</active>
<children>
<child lootmax="4" lootmin="3" max="5" min="5" type="Land_Wreck_sed01_aban1_police_DE"/>
<child lootmax="4" lootmin="3" max="5" min="5" type="Land_Wreck_sed01_aban2_police_DE"/>
</children>
</event>
Параллельно заработал и ивент StaticPoliceSituation.