> (x) delete, obscure, or in any manner alter any brand features, logos, warnings, notices (including but not limited to any copyright or other proprietary rights notices), or links that appear in the Service or the Content;
This appears to be the newer "embed" version of Google maps, which is the source of your UI clutter.
Just use the API and you get no "view on google maps" and you can turn off the zoom and satellite control with disableDefaultUI: true. You still have the copyright line, but it's not really that intrusive.
A better way to achieve this would be - Detect the map params which should be trivial because embedded maps have them as get parameters. Now use the JS library to replace the embed with the map you get via the library. You can disable all the clutter as well as interactive features while doing so. And you won't break any TOS.
If you must go down the road you're on, might I suggest shipping this as an extension rather than a library. Very few developers would break TOS by using this but a lot of users might still love it!
Probably not a big concern for a personal portfolio site, but for most applications this is a bad idea.