Root Problem: Moldy and Shriveled!

[Abbyr20]

Hello Everyone,
Thank you for reading this. I purchased a Phalaenopsis orchid from a grocery store a few weeks ago. I did not know anything about them when I bought it, so I did not know what to look for. The original vase did not have any drainage holes, and it stayed in that for 2 weeks while my new pots were shipping to me. I just re-potted it in a well draining pot, but a few of the roots are moldy! I do not know what I am supposed to do. The plant itself seems very healthy, but those roots do not look good. I will include a picture of the roots. I just need to know what to do! I am very worried.

Thank you!