Hi Elliot,
Same problem here, I believe this should be marked as not resolved, as Matthew reports in his edit above, it’s not solved for him either.
TinyMCE does not load on posts where ACF WYSIWYG field is enabled.
I too initially had a problem because I was trying it with TinyMCE advanced, but I just tried ACF on an installation without that plugin, and the tinyMCE is still disabled
