Your question is well phrased: you have asked for a confirmation, which Youtube has not supplied. That amounts to a tacit admission.

I would suggest using it in a story where you clearly outline your question as well as the answer, and point out that the response does not answer the question. Or you could send out a follow up email:

"Your response, does not contain a confirmation that this ToS change was NOT initiated or modeled in relation to a YouTube API powered website called Totlol (totlol.com).

In the absence of a confirmation, or response to this email, we will go ahead and accept your response as a tacit acceptance that the ToS change was modeled in relation to Totlol.com.

Again: Can you positively confirm that this ToS change was NOT initiated or modeled in relation to a YouTube API powered website called Totlol (totlol.com) which has launched two months prior?

Warm regards, etc."