It's not about believing ILFJ. You can't simply recruit the guy you want. You pick three, and the narrator gives you one randomly (unless you know who the BG and D are).
Until then, the real lawyer would be doing the Cs a big service by exposing ILFJ as a liar.
Of course but revealing yourself will make it that much easier.
Also ILFJ does all kind of retarded shit on day 1 and you explain it all "because he's crazy, I dunno lulz". How about some real explanation about:
1. fake account
2. lying about pms
3. revealing he's a lawyer when he didn't need to do it at all
I mean how don't you at least wonder about this if you are a C?
The only way to check if he really is the lawyer would be to tell him to save the next lynching victim. But that's wasting one save if he really is the lawyer. But at least we would know.