Do all Scrypt coins on Zergpool support merge-mining with DOGE?
Not all, we have special image next to name of the coin, specifying when coin supports merged mining
I think the question may have been misunderstood. The coins with the merged mining symbol are the merged coins.
I believe the real question is whether all the main coins support merged mining.
From what I can tell all the merged coins will mine along side any of the main coins. But I stand to be corrected.