I know the "budget" Ernie Ball strings can be hit and miss but as I bought a 8 string I went with a familiar name and the gauge was around what I was after too.
I've seen this in the past so its not an exclusive issue with Thomann for sure, but getting the new strings out of the pack parts of the string have already weathered (whether (ha) that is the right term or not I'm not 100%) but parts of the string (lighter) have rust marks on them new out of the packet.