Is OP statement what you consider 'evidence'? Yikes....
He merely made some statements, some of which were facts (Pet does indeed have CC) and others were just... opinion and/or false statements.
(The pet can CC but not neccessairly WILL counter CC if you CC).
All in all, this were not at ALL evidence, nor even a strong case for Summoner being OP.
Let me break it down for ya aye.
1) He did not have ANY numbers on ANYTHING that summoner has.
What <insert stat> does Summoner have? How does it compare to others? What's the damage, the range