I had two previous marriages and a 30 year age difference, i asked this to the VO at ACH she said it was not a problem, my guess is because of front loading ,my wife was not asked anything about my past marriges at her interview
Its not a problem I was 58 and my wife was 28 when she had her interview, but i did bring this up at Ach in guz an the V O told me they look at age but no problem if you prove relationship