U_A, thanks for posting the relocated chart with transits.
In medical astrology Leo and the 5th house rule the spine, with Saturn more generally ruling your bones. The first house more generally rules the body; and the 6th house, one's health. It is interesting to see all those transiting planets lining up in the 5th house for the time and date of the surgery, with Leo on the ascendant.
Jupiter in the 5th house, very strong in its domicile, looks like a real good luck factor. I checked, and the part of fortune is there, as well.
May I ask, TTD, is there anything going on re: your fear of the surgery, that specifically relates to this particular surgeon? A surgeon is represented by Mars, and Mars-Neptune is where the squares on the event chart are coming from. This doesn't mean that the surgery will go awry, only that a chart tells us a lot about the querent's inner state, as much as it shows the externalities.
Again, the event chart on its own isn't so helpful, because it would be for the entire population of the greater Seattle metropolitan area. We want to look at how it relates to your (relocated) chart.
Then one of the troubles with event charts, is that there are very few days on the planet where an event chart will look completely wonderful. There will always be something going on up in the sky that we'd rather not have happening on an important date; but if we change the date, than something that looked good in the first chart goes away. Then the outer planets stay in one place for a very long time.