If you look closely at their Github, you can see that branches for Pie has been created for the vim3, we can only hope that the pie source code for the vim1 and vim2 comes out shortly after.
@Gytis@zdesautels We will release VIM1 Pie source code after one or two weeks. About the VIM2, we haven’t the plan to update to Pie because the amlogic official still don’t release Pie for VIM2(S912).