I have similar incidents and always eventually received my credits following these steps.
1. Expand the offer where the requirements can be clearly seen and screenshot.
2. When you are taken to the web page for the product offer take another screen shot.
3. Take a screenshot of the item in your shopping cart and another showing the item was purchased.
4. Finally take a screenshot of the confirmation email.
This will need to be disputed through Tapjoy. help@support.tapjoy.com
Same when taking a survey.
1.Take a screen shot of the entire screen where the date and time in the lower right hand corner of you screen clearly shows the time and date at the start of the survey.
2. If you spend more than 20 minutes answering question only to get a message that you do not meet the requirements for the survey, take another screenshot with the time and date and dispute that you spent 20 minutes or more and we’re then booted from the survey.
I have been given the credits offered on a 2500 credit survey by disputing my wasted time.
This will need to be disputed through WGT.