Welcome to ATP!
I'm just guessing, but I guess that your best chance of reproducing that exact lily is better if you pamper the bulb or roots for a few years until they get spread and get big enough to divide the roots.
If there are multiple bulbs, each bulb can be a new plant. If it has big thick roots (rhizomes), those can probably be divided into a new plant. Multiplying it that way assures you will get more of the same plant.
Propagating that way might take 1-3 years of good growing conditions, including a big pot and good aeration and perhaps fertilization, or growing "in the ground" with suitable soil.
Some lilies are "self-infertile" so the seeds in the pods MIGHT not be viable.
Even if they are viable seeds, they MIGHT not come true to their parents: you might get a wide variety of offspring plants, none as fancy as the parent.
That's about all I can suggest. If anyone else suggests something that contradicts what I've guessed, trust them! I'm going mstly from reading and hearsay.