How does Allen Kane protect Henry in the novel, Unintended Consequences?

Allen Kane and Henry are good friends, so when Allen and Henry discover that the ATF intends to raid their homes, probably plant evidence, and imprison them both, Allen arranges for a western trip for them both. Allen goes ahead, while Henry proceeds to the home of another dealer to be raided, surprises the ATF and kills them, returning to his home to take out the three ATF helicopters that are landing on his property. Allen is Henry's alibi, stating that Henry has been with him on a prairie dog hunt.