How to insure my data is safe when trading in an iPhone that I was not able to erase?

I’m not technologically inclined and I’m trying to determine how safe my data is on my phone I traded in. For one: my phone is broken. The back is shattered and a quarter of the screen is white with lines so trying to type in a passcode is nearly impossible. I tried for hours to see if I could unlock it with no luck. In order to trade it in I needed to remove it from find my. I clicked the erase device option, but my phone could not connect to the internet without putting in the passcode to erase which I obviously could not. So the date in which my phone had to be removed from find my happened before it could get erased.

So my questions are:

will my phone still erase since I opted for that option if it some how connects to the internet even though the device was removed prior?

also I know it takes off the activation lock when you remove the phone from findmy but does the passcode stay in place?

how safe is my data?

thank you for any information to ease my mind!

[Re-Titled by Moderator]