I had an opml file with 120 podcasts in it and one of the feeds had an expired api key or something that couldn't be reached. The invalid entry was the 3rd podcast in the list of 120 and only the first 2 podcasts in the file were imported. @mogwai recommended I log this, for developers to consider a different behaviour, in which the invalid feeds are ignored and the rest of the import would succeed.
I checked the opml file that you shared privately. The issue is actually that that file itself has an issue. The third feed contains a literal ampersand in the URL, which is not allowed in XML documents. This should have been replaced by "&". If I make that change, then the file imports without any problem. Maybe it's good to report this problem upstream with the app that you used to creat the incorrect opml file?