I found Vout image for internal soft start on datasheet.
Can I leave the SS pin open ?
According to the ADP1754/55 Reliability Report, the ADP1755 passed ESD Levels up to (also see attached image below):
FICDM Passed up to +/-1500V
HBM Passed up to +/-2500V
MM Passed up to +/-200V
I'm asking someone to try to take a look in the lab, see if we can duplicate; I can't right now. The latest details you provided may make your question about an alternative regulator largely irrelevant, but I was able to get a recommendation for…