Yes, it is correct.

My EAD renewal was rejected. The reason is "The check amount is incorrect, or has not been provided." I provided a $340 check.

Was the rejection based on "Dept of Homeland Security" I wrote in my check?
-It is correct to make the check of $340 payable to Department of Homeland Security for the EAD filing. However, if your I-485 filing fee was $1010, you do not need to pay the fee for EAD renewal/application any more no matter how many times you renew your EAD or AP. If you pay the fee with your application, USCIS will reject your application.