[Castiel doesn't get the comment but doesn't even bother to, and just turns toward his brother.]

There was... Something I didn't inform Lucifer of about the tunnels, and he found out. He's no longer speaking to me, but that is not the particular issue.

[It's not great, but also not something he needs Gabriel's help on.]

However, without me involved, it is logically wise to call the entire plan until it can be reworked.