Install another Java 8 build:
https://www.azul.com/downloads/?version=java-8-lts&os=windows&architecture=x86-64-bit&package=jre&show-old-builds=true
Scroll down to 8u302b08 and install this build
Then edit your bat file and use:
"C:\Program Files\Zulu\zulu-8-jre\bin\javaw.exe" -Xmx8G -jar forge-1.16.5-36.2.20.jar
Pause