I cannot find references if the Delta IV heavy 7 except on this wikipedia image. It consists of a Delta IV heavy with 6 boosters. There may be a need for such powerfull launcher (otherwise the SLS' developpement would not have been started) but no reference to it on the wikipedia list of current and futur super heavy launcher. What is the current status of this launcher?
ULA presented the 6-booster "Delta Superheavy" in 2004 (archive link) as a possible upgrade path for the Delta IV.
As far as I can tell, it's only a proposed design. Actually building it would likely require structural changes to the core stage to handle the additional stresses (as we've seen with Falcon Heavy), and the launch pad infrastructure would have to be changed to support the new configuration.
The Delta growth options paper is attributed to staff at Boeing who work closely with NASA, so my assumption is that they would like NASA to take an interest in the options.
Since the 6-booster Delta is in roughly the same payload class as Block 1 and Block 1B SLS, it's unlikely that it will get support from NASA at present. If SLS fails completely, ULA might try to push the proposal again, but it couldn't be evolved to support payloads in the Block 2 SLS class.