I'd definitely ask them more about the process/documentation/etc, after all it is your car, you're paying the money they should be able to divulge.
When I had my Kia they recommended a "fuel induction cleaning" - I researched and researched it, since the dealer wanted $150 to do it...turns out the process was almost IDENTICAL to the service that Walmart does for $20, or $40 if you get the Lube Oil and Filter job done WITH the fuel induction cleaning.
Only walmart calls it a "Fuel Injection Cleaning".....was provided by GumOut, but now I've heard select stores have switched over to a Valvoline service that is considered "No Smoke" as in, it won't make the huge exhaust smoke cloud ala seafoam, MMO, etc. through the intake, but the process is nearly exactly the same as what the dealer described to me. They got a concentrated bottle that goes into the fuel tank, and a bottle that hooks up to the intake, either the PCV valve, the brake booster, or EGR valve (in that order) that hooks up through similar to that of an "IV drip" and they set the drip "just right" so that it won't flood the intake, or cause it to stall.
Likely only difference is "chemicals" they are using for the process.
If you look online, there's a myriad of solutions that'll do this. What's funny is Gum Out has NO mention of this "2 Step Process" on their site (perhaps they just backed down, and were just working on getting rid of old stock to Walmart?), I know Berryman's B-12 CHEMTOOL has a similar mechanism is they have listed on their site/catalog, as does the big guys over at BG-44K...and even SEAFOAM has a new similar product, only there's hooks up between the air intake boot, before the throttle plate (butterfly valve), and you lock the canister in place, and let the car idle.....cleans up the throttle plate and the intake supposidely real well, with no need to go messing with vacuum lines, etc...so it's a tad "easier" no need to mess with loosening hose clamps, etc....just start the car up, engage the can (it's got a locking cap thing, but it's preferred to have 2 people, one to adjust the gas pedal from inside the car, and one to watch the can.....). and then 3M even has a process of there own too, that looks very similar to the Seafoam product, hooks up between the air hose boot, and also comes with another solution for the tank....
I'd ask the dealer what product they are using....
Since there a couple "over the counter" options to be had...
Seafoam Spray - that's the new product name lol, I saw it at Advanced for 9.99 a can, and it comes with the cool "curly straw" that hooks between the air boot.
3M - I can't recall the price, it may have been $40-60 through their online web site....
GumOut and/or Valvoline 2-Step process - $20 at Walmart TLE
BG44k - not quite sure on the price, I'm guessing it's in the $60-$100 range - they have "select" shops around my area, but never looked into it to get prices.....don't seem to have any way of buying the product directly from them....
Berryman's process - again, no prices listed on their site, their catalog is geared towards shops.
3M and BG44k are likely to be about the best of the best though....with the Berryman's being a close 2nd/3rd
As far as the "engine cleaning" - I'd be weary of that....lol, as I'm not a big fan of "fast flushes".....