It's bad enough when query letter writers refer to themselves in the third person. Here's an example of what I mean:
Dear Barbara Poelle,
Janet Reid has written an enticing fiction novel about the value of vodka in conducting high stakes literary auctions. Would you like to read it?
If you are writing the query letter, use first person "I have written."
That's a rule. No exceptions.
Knowing that, when I get a query from someone who says "Janet Reid has written" and the email address and the signature are a different name, I think one of two things:
1. You have multiple personalities
2. You aren't the writer
1 is preferable to 2.
You can't query for someone else. Not now, not ever. I won't respond to those queries. I've said so before, and so this is just a reminder.