Well, I think there are ways to do it
I think you can use the 'bind' builtin command (see info bash >> Shell Builtin Commands >> Bash Builtins), so you assign to the 'insert' key the behaviour you like. Something like this
bind -x '"\ooo":"theFunctionYouWant"'
where \ooo is the ascii code of the key (in octal).
The bad news: I don't know the codes of such keys; moreover, this recipe only works inside a bash session
However, if you want full control over the keyboard, I believe you should go to the X server documentation; perhaps you could begin with 'man XF86Config' and the references therein.
I hope it helps you to begin the search.