Help!

"On behalf of Prof Ruiz, I confirm his attendance to the meeting"
I need to know if this sentence is correctly written.
Thank you!!

It is stated well but I would add hlightighted.

Help!

"On behalf of Prof Ruiz, I confirm his attendance at to the meeting"
I need to know if this sentence is correctly written.
Thank you!!

Help!

"On behalf of Prof Ruiz I confirm his attendance to the meeting"
I need to know if this sentence is correctly written.
Thank you!!

I see a lot of people use "Prof" to mean Professor. In the United States, this isn't used. I would rewrite this sentence in one of the following manners:

Speaking on behalf of Professor Ruiz, he will be attending the meeting.

In proxy for Professor Ruiz, he has confirmed he will attend the meeting.

Concerning the meeeting, Professor Ruiz has agreed to attend.

Professor Ruiz is aware of the meeting and has said he will attend.

=-)