The Survey Level will hardly increase the probability of high quality, only allow you to obtain high quality but no make it easy. Troubled by an epic exhibit million times is just potluck. 

 Moreover, the pseudo-random system is also awful. It always just lack of the last exhibit which just ready to pristine, it makes the pristine exhibit you need never comes from the showing rewards.

Those problems are most evident in the antique expedition of Bungle Burrows, where the Printing Press always “Find more pieces to complete this exhibit!”.

 I don't know it is bug or any other thing, just stop letting each location only left an epic exhibit forever.