Very much looking forward to seeing this in a future National Exhibition!
Interesting that you found borers. I've been having a major problem with them the last couple of years. They killed back the top of a styrax, a couple of mimosa (albizia), a magnolia, and a trident this spring (all in the ground, so far no problems with potted trees). Some kind of very small black/brown beetle, they bore tiny holes into the trunks in early spring, infect the plant with a fungus, and the young grubs live off the fungus. There are many similar beetles so I'm not sure if these are shot hole borers, granulate ambrosia beetles, or something else. In any case, they can be very destructive. I hope you burned the branches that had them inside, though most likely the beetles are already in your area.
Chris