I don't see any reason for you to oppose support for the flag.
The Flag wasn't created correctly.
As you yourself point out, the flag creator is not the one who created the thread. Therefore it can be locked without intervention by the flag creator. The OP of the thread you pointed me in the direction of has no flags listed, so no Flags supported.
Okay?
Deciding not to support the flag is one thing, but you're opposing support for it which only serves to give credibility to the scammer.
And besides, I don't see any issue with creating a flag that references a thread that you didn't create - we don't need another Betking scam thread and Jollygood creating another identical flag just seems redundant.