No start no crank after kids played with door entry code buttons

So my truck ran fine I park the truck lock the doors my kids
went out there and decided to play on the pushing all the
numbers on the  keypad  when I caught them the keypad
was flashing so I grabbed the key fob unlock the door open
and closed the  door  locked the truck up and  the next day I
went out to start it and have full power but no cranking I
hear are all the clicking inside the the cabin and under the
hood but it will not crank everything else works fine lights
heater and stereo. Now I don't remember my anti-theft
device flashing when the truck is locked with no keys in it
but it does now, but it does go out when I turn the key over.
So I have done every reset that I could find online by turning
the key on off eight times using the key fob panic button
unlock and lock buttons I've checked all the relays and
fuses I have disconnected the negative terminal for an hour
then disconnected the positive terminal for an hour then I
have disconnected both of them overnight I have tried
everything and I have haven't had any problems with the
vehicle starting or dying on me till this keypad thing so  my
question is even though I've got 12. 4. volts at the battery
and 15V when I attach the battery charger on it and  select
40 amps to try to start the vehicle, could the battery still be
the issue. Only reason why I think that I have a 4-stroke
snowmobile and I had the same thing happen all test
indicated batter way good and charged and even trying to
boost the battery while turning it over the sled would not
start by luck I put a new battery in and it fired up.
Also do I need to get a scanner code reader and plug it in
and reset my codes and maybe that will let me start the
truck any help would be useful thank you