I prepared the simple project which shows the problem. I modified tapjoy SDK demo project. I added there only grandle and proguard rules. Here problem occures: https://github.com/klakiers/tapjoy-proguard-problem
Proguard file: https://github.com/klakiers/tapjoy-proguard-problem/blob/master/app/proguard-project-debug.txt
When proguard works turn off everything is fine. Offerwall shows offers correctly.
This resolve the problem! -keepattributes Annotation