Back from the Brink and Shadowfield.

I use the stratagem back from the brink in an archon when resurrect, the miniature retrieve the shadowfield salvation?

Hmm.
I think not, as the intention is clearly that the target is saved from death, and isn't set up as a brand new unit. As such, if the Shadowfield has already failed, it remains failed.
Its a good question worth directing at the FAQ team though.