If you have question about the arcgis online layers, you can ask whoever published this layer.
But because of you are not their organization, you can't sign in to their arcgis online account.
When you click their profile try to find their email, you will not be able to. You will get a page not found error, since you did not login to their arcgis online account.
You still can find their email by their Arcgis online account profile by hove your mouse on their profile link, the link will show at bottom your browser, see below. Or you can right click link, choose copy link.
Just remove the rest of char after .gov.
The correct email will be SJulius@isd.lacounty.gov without _lacounty.
"_lacounty" was added by ESRI specially for her arcgis online acount in ESRI domain.
