I'll add a few comments which you may find helpful.
1. Group 27batts provide around 95 amp hours each and since you may run them down to 50% before they need a recharge...you have a built in 95 amp hours to run your fridge.
2. If you are only going to have 2 batteries...12V true deep cycles are the way to go since if ONE fails...you can STILL run the fridge off of one. With 2 6V batts...if one fails you are up the creek without a fridge.
3. The average modern fridge will use roughly 10DC amps while running. More with defrost on. This means for every HOUR the compressor is on..you've used 10 mp hours. From ambient temp to everything below 40 degrees...you'll have the compressor on full time...so if it takes 4 hours to get to that point...you've used 40 of your 95 amp hours before you start your trip. PLUS whatever your inverter eats up... and whatever OTHER ac or dc needs you have which might in total add 5 amp hours while you are just getting to operating temp.
4.Once op temp is achieved...most people report around 1/3 to 1/2 time compressor operation but outside temps and how often the door is opened will affect this a lot. 24 hours would mean 8 to 12 hours of run time @ 10 amps x hours or 80 to 120 a/h per day. Which is why those who boondock generally will add more batts. Otherwise...two is plenty.
5. My G'town has a 55amp converter which I assume is the same as you have. Figure 4 hours of genny run time to fully recharge your battery bank if you discharge to 50%.
5. Once you are underway in the coach, your alternator will be continuously charging your batts so you have no worries about the drive. Your built in generator is another source of charging power since it powers your built in converter/charger. If you can use a voltmeter... just turn the engine on and check at your battery terminals for over 13.2 to 14.5 volts which will mean your alternator is charging the house batteries. Otherwise...run the genny down the road and don't let the gas tank get below 1/3 since it will shut the genny down at 1/4.
Sounds to me like you are in good shape to keep the food cold and the batteries topped up. If you boondock rather than plug in you might consider a 4 pack of 6V batts...but otherwise you should be good to go.
2015 Georgetown 280DS
2014 Vespa LX150 2014 StellaAuto 125