You don't need that.
Anyone with basic understanding of how business works will know that you have far more profound experiences than most corporate ladder climbers.
Not true. To most corporate recruiters 'doing a startup' for a couple of years is almost the same as being unemployed. I faced this myself after years of slogging away at an unsuccessful project and then trying to get back into the job market.
Things that people in start ups don't know: getting technical things done in complex environments. I would focus my CV on showing interaction with corporates outside the firm - show you have some game.