It does have a built in skip though I know it's not the best. Unfortunately I do not have the time to 'fix' it.
You can minimize this issue by doing some of the following:
If you are leader, make sure your leechers are not hitting the seals before you
If you are leader, make sure you run a small script BEFORE diablo. This resets the points in the chaos sanctuary and helps prevent the sealnull.
If you are a leecher, run diabloleechfightnoseals.ntj instead of the regular leech.