For me , if a maul has entered in goal legally , i would play on & see what happens ..
If it gets pushed back out ,,i would play on .. ( shout loudly ,,thats once to attacking team )
I dont beleive the laws are saying you cant have a maul in goal , to mean in that context .
So i would allow a maul to be collapsed in goal , by deffenders ,,as the laws dont apply in goal .
I would also allow entry from side , once ball over line
The very same as it says you cant have a tackle in goal .
Its not that you cant tackle a player in goal ,,its the laws around tackle that no longer exist .
Such as no gate entry required ,, tackler would not need to get off floor , to legally handle ball ..