Default send it in?

ok i have a sprint g2 that i have all but given up on. i rooted it and upon rebooting and flashing the recovery i have myself a half brick. can get into download mode and if i really get lucky fastboot. however, fastboot is nearly impossible. so heres my question. if i play dumb with lg will they warranty this? or will they detect root and tell me to pound sand? i have read something about trying with an otg cable but im not even sure that would work.

what do you guys think?