Is this proper English?- I would like to speak to the Executive Director about my daughter's experience, and my experience, at the center".

"I would like to speak to the Executive Director about the recent experience my daughter and I had at the center."

Yours is grammatically correct. Mine just flows a little better.

No, you need to remove the comma after the first ‘experience’

No.

I wish to speak with the Executive Director about the experience of my daughter and myself at the centre.

It's fine. You could also remove the commas and it would still be okay.

“My daughter’s and my experiences”

Thanks! What did they do to you?

Lmao 😂😂😂😂