What's your question? Ask

Asiatic lilies can be grown in zones 4-9. Or 3-8 or 4-10 depending on the information source. Hardiness may vary with specific hybrids. If you are on the edge of hardiness zones, buy from local nurseries or local mail-order firms. It is in their interest to have happy customers and they will stock hybrids that are hardy in your area.

Yes, you can plant them out after your frost free date. You have a plant, not just a bulb so the plant needs over-ride the bulb advice. Take a week to slowly get them acclimatized to outdoor sun, wind and drier conditions.

Asiatic lilies, like other lilies are "one and done". Different varieties may bloom at slightly different times, extending the bloom season. Check out the article on bloom times of several hybrids using this link: https://www.gardenia.net/plant/lilies-for-long-summer-blooms

Pests can be treated with Neem Oil.

Rust is a more difficult issue.
These articles will help you.

https://www.gardeningknowhow.com/plant-problems/disease/learn-about-plant-rust-disease-and-rust-treatment.htm
https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm

Yes, they may have diminished blooms next season, but the bulbs will survive.

It's difficult to say without seeing the plant and flowers.
The bulbs could have been miss labeled or the plant may be stressed or be suffering damage from pests or disease.
Upload an image and we can take a closer look.