Correct on both accounts. The round scratches along the barrel are indicative of forced dull cutting tool; the clear and dull spots on the brass tube means that it did not have enough glue adhesion.
As to the glue, Epoxy will fix it to some extent but the best way is with polyurethane glue over night. Epoxy still creates air pockets between the tube and blank if not careful. One great advantage and disadvantage of CA is its quickness to set. Because the tube is locked in - does not mean it has great adhesion, and gives a false sense of security. Yes, there are those that swear by the CA for tubes and have never had a blow out, but they don't say how patient they are in making it secure, or how they let it cure for several hours before turning.
Another "catch" is that "making a pen" can give quick gratification. That "drawing us in to make a pen" just about obscures the importance of maintenance with tools, in which tools require at almost every point. I do not use carbide inserts much (but I do use them some), but for those just starting our, I think it is the best. Too often, the desire to complete "one more or two more" pens overcomes the need for sharpening tools or good preparation. A good sharp carbide insert will do maybe a dozen pens well on one side before needing to turn it to an unused side. This allows the turner to get some experience under his or her belt before learning to sharpen the tool. If using an HSS tool, Sharpening or at least honing between Every Pen at the most is a requirement. If not done, the results will be as you experienced.
I should add that Pink Ivory is more brittle than the "average" wood.
I definitely will use it for something. Not sure what just yet, so it will go in the "scrap" bin for now.
The segments were glued with CA, but I use Gorilla poly glue for the tube inserts. I still have a lot to learn about sharpening. I do have a couple carbide chisels. They seem more for scraping than cutting. Guess I'll have to watch some YouTube video tutorials on them, but I'm always open to tips.
Is that a one piece blank for a sierra kit or something like that?? Part it off and add either the same pattern as the upper or maybe a black end or do scallops again and just cut to fit. So many things you can do without destroying what you have already. The beauty of segmenting is there are no mistakes just design possibilities. Show us your talent. Good learning opportunity.