Your rooted cutting should be fine. Crown Gall is due to a bacteria infection that gains entrance thru a tiny wound in the bud union, root, or cane. The bacteria is in the soil. Removing it and replacing with new doesn't get rid of the bacteria. It's in most all soil or will be if the soil you replaced the old with happened to be free of it. Doubtful!
I've successfully excised the gall resulting in a clean healthy bush with no reoccurence. Avoid nicking the roots, bud union, or canes when working around them to avoid infection. An insect or rodent bite can even be a entrance wound for the bacteria.

Karl is absolutely right on here. This is an unfortunate event and is not infectuous to any other roses in your garden unless they get injured and allow this particular bacteria to enter that wound. I have successfully replanted roses in holes where I had a previous gall infection without incident. I did dispose of all the soil I could when getting rid of an infected rose, replacing it with a mix of good garden soil and native soil in the hole. I have heard that some even treat the spot with a bleach solution, but I think that is a bit extreme and might end up doing more damage to other beneficial organisms in the soil that are necessary for growth of a new rose.
John

Your cutting is fine, don't throw it out.

Go ahead and replant in the same area. Crown gall bacteria are everywhere so there's no getting rid of it. Just avoid injuring the plant as described above.

Yeah the galls are ugly, but not all that scary. Not contagious in the normal course of events.

Thank you. I don't feel so bad now. I was just really starting to feel down when I saw such a horrible cancerous-looking growth and it was depressing. I dug it out and disposed of a lot of soil just in case. I think I'll plant an annual in its place for now. i do still have the cutting and it's ok in the pot for quite a while.