There are so many computers in these cars I'm honestly not sure where each option comes from. I believe "most" of those features are stored in the BCM and perhaps with a tool like AlphaOBD they could be enabled, but I have no experience there.
When I dug around in the 8.4AN(old uconnect) I was able to enable all kinds of neat things on a Chrysler 200. Performance pages, or make the radio boot up as though it was in a viper.
alfa OBD came in when I wanted to add turn signal mirrors, or convert the 5.0 radio to an 8.4 unit.
Want performance pages on a v6 charger? Radio edit.
Want to add heated seats or memory mirrors? BCM.
So if you need to enable a new module on the bus, that's going to be alfaOBD(or dealership) and a BCM update where you enable the option and proxy align to pick up the new module. Things like uconnect are only in the radio. I have not played around in the newer system yet, so some of this could have changed. I think its unlikely though.
I would bet the reason this swap won't fix the 3g issues, is the same reason you can't add uconnect to a car that didn't have it from the factory. The computer on the subscription end won't take the vin. The antenna is exactly that, an antenna. Just like "HDTV" antennas are just the same dumb antennas grandma had in a fancy new form factor. The 3g important parts are on some dinosaur Sierra wireless card IIRC in the old 8.4.
Yeah 3g and 4g aren't on the same exact RF bands but I'm not convinced Chrysler would bother with tight bandpass filters that you couldn't get 4G on the old sharkfins. It might be weaker signal, but it'd work. Unplug your cell antenna in the car and I bet you still get some cell signal if you're in a densely populated area.
Nice work on the swap
@Speedy!