HELP Very confused on installing an APP, on upgrading Android

We got our son a Venue 7 Model 3730 tablet so that he could play his Skylanders Trap Team game made specifically for tablets.  When we went to set it up, it told us to get the free app and install it.  It wouldn't let us saying that it needed Android 4.4 or higher.  So we went to (About Tablet) and noticed that it was 4.2.  We did an upgrade and it took it to 4.4.2.  So we tried again, and no luck.  It said that it would not support the model 3730.

We then tried it on my tablet which is a Venue 7 Model 3740, and runs the 4.4.4 Kit Kat, and of course it works.  So we were wondering if it is  possible to put the 4.4.4 Kit Kat on the sons tablet?  Or if we are doing something wrong in trying to install the free Skylanders app?  Any suggestions would be great.