The steps I provided above where for the latest version of CalyxOS which I do run on one of the devices currently in my possession. What I mean, is that I tested it myself before replying to your post. If you are also running CalyxOS and the SIM card doesn’t not appear as an import option in the stock Contacts app that’s really strange.
Either way, seems like you did find a solution to your problem. So, glad to hear it.