No extended service plan is going to be bumper-to-bumper. After your basic warranty expires it is no longer a warranty...it is a service contract.
I'm all for peace of mind but read the fine print to make sure you know what you are getting into. Lots of stuff covered but not nearly as much as the basic (new vehicle "bumper-to-bumper") warranty.
Mopar does not offer a "Platinum" version so the dealership is offering a 3rd party plan (they make more money on them than Mopar MaxCare policies) or it is something the dealership itself is offering. If that is the case then that warranty would only be honored at that dealership. Sometimes it can be a good deal (great marketing for the dealership - you get your work done only with them, they can upsell you, and you are more likely to buy something off their lot since that's where you go for all your service work) but the down side to those is you might be out of luck if the ownership changes.
There's a couple of car dealerships near me that offer perks. One has lifetime loaners if you buy a new vehicle from them and another has "Lifetime Warranty" plastered on every window on the lot (new and used). My wife thought that was great until we stopped to ask about it and the "Lifetime Warranty" is actually a (very) limited powertrain warranty for as long as you own the vehicle...and have it serviced there.
Fair enough, the MaxCare warranties are a service contract of sorts, though I think it's more like an insurance policy - it has a $100 deductible each time it's used, per service writeup, not per issue (the last time I had my sensors fixed, I also had the transmission gasket and pan replaced, and only paid $100). And depending on which MaxCare you purchase, it CAN be bumper-to-bumper for FUNCTION, not form - my Lifetime MaxCare didn't cover the words wearing off radio buttons, but it DID cover if the radio buttons stopped working, for example. It also doesn't cover routine maintenance such as oil changes, brakes/rotors, etc.
You're also right that Mopar doesn't offer a 'platinum' level, they have different wording for it, because they do have Powertrain-only, Powertrain and electronics, and bumper-to-bumper levels. I don't recall what their wording for each level is. Regardless, it sounds as though OP bought a 3rd party extended warranty, NOT a Mopar one.
Every dealer has their gimmick to draw people in and drive sales. It's part of the game to stay in business. One near me says 'no pressure, no hassle' but I almost never get the best deal there unless I'm walking in with a supplier discount number, because that price is dictated. Another claims you can buy anything from them (and you literally can, they carry just about every major brand) but I'd never go there for service because their service department has to service all of them - sorry, I want someone who focuses on Mopar stuff touching my truck, not someone who normally services multiple other brands and might get themselves confused. If I want a general mechanic I'll head to a different shop or do it myself, if I'm at the dealer I want a Mopar mechanic.