I don't think being hired by Burdon would have been good for Justin at all. Burdon does all his own vocals--I think he runs his own show and stars in it. Plus I don't think Burdon did a lot of songwriting himself--he did covers of blues tunes (House of Rising Sun, We Gotta Get Out of This Place, Don't Let Me Be Misunderstood, etc. were all written by other people). So Justin would not have been encouraged to do vocals, nor do I think he would have been stimulated, in the way he was by Pinder especially, into great song writing.

Burdon with Hayward would have been a continuation of the Moody Blues Mach 1, basically (ex: Tobacco Road, and the other songs mentioned above). For Justin it would have meant doing more of what he had already been doing for Marty Wilde--back-up guitar work. I don't know if Justin would have had the confidence at that stage to have insisted to Burdon that the band do some of Justin's songs. I think Justin would have stayed for awhile, and then the songwriter in him would have forced him to leave and either go out on his own or find another band.

Thankfully Burdon didn't hire Justin, the Moody Blues did, and the rest is history.