Modify header on multisite to add iFrame content

I’ve been tearing my hair out wondering if this is possible…

Add iframe or ‘<?php>’ ‘if’ code to the header.php file but be able to make it display different items on different sites on my multisite.

E.G. ‘if page_name = Radio 1 = <iframe src=”header.php”>’ ‘if page_name = Radio 2 = <iframe src=”header2.php”>’ and so on.

I’ve tried using plugins to add to the header however they appear above the logo and that’s something I want to avoid. I want the iframe to sit beside the logo.