Welcome to the forum. Thanks for your question.
There are around 40 types of HPV that primarily infect the genital area and are sexually transmitted. Gardasil protects against 4 of them, including the two that cause about 90% of genital warts and two others responsible for around 70% of cervical cancer. Against those strains, it is among the most effective vaccines every developed, against any infection. But most people immunized with Gardasil will still get HPV due to the many other types not covered by the vaccine. Fewer of them will have problems with warts or with abnormal pap smears, but there will be plenty of exceptions -- as you have experienced.
Clearing of warts after only 2 weeks treatment with imiquimod is a little atypical, but well within the normal range. You can't make any accurate judgments from online forums, including this one. Online forums tend to attract people with atypical experiences.
There are no hard and fast rules about disclosure of past HPV infections. Below are links to two thread that discuss the issue in detail. In general, I don't think it's necessary. For every person with diagnosed HPV, there are 10-20 others who have had HPV (and may still have it) -- so informing partners doesn't materially lower the chance they will be infected. But it's a personal choice that you'll have to make for yourself.
And as for "shame" for being diagnosed for warts, there is simply no shame in it. Probably 20% of all Americans have diagnosed genital warts at one time or another.
Finally, could you catch HPV again in the future? Sure. Is it possible you could have yet another wart-causing infection? Quite unlikely, but possible. Getting genital HPV is unavoidable, except in celibates; it's a normal and expected consequence of human sexuality. And therefore certainly nothing to be ashamed about!
I hope this helps. Best wishes-- HHH, MD