ASA Rules - No slide at the plate.. is ball dead ?

[WeekendRef]

Last night while playing in a rec softball game there was a situation that arose that I was hoping somebody may give me some clarity to . I will let you know up front that the call went against us but I was not upset because a) it is rec softball and b) we were losing by quite a bit anyway and this had no bearing on the outcome .
Situation :
Runner on second and first and there is a base hit to right field and there is a play at the plate . The ball and the runner get to home plate at the same time . The runner does not slide and knocks the catcher over . The ball then gets away from the catcher allowing the runner who was on first as well as the batter to score . The runner who was involved in the play at the plate is declared out because he did not slide (It was not malicious...he just ran him over) .
Question :
My question is should the ball be dead at this point because the runner did not slide ?
My opinion :
From my perspective if the catcher was not knocked over the the ball would not have gotten past him allowing the other two runners to score .(Actually the ball probably would have gotten by our catcher anyway because he really does not live up to his position title but lets assume he can catch a little bit .
HELP :
Trust me I have no problems if I am wrong I just want to understand this a little better . If somebody can provide the rule that covers this (If there is one) that would be great .