Hello, Marie,
Thank you for your response.
It is impossible to do with CSS.
As our builder uses own hooks some code from extra plugins should be modified and added by Code snippets of child-theme/functions.php
For this time we copied the solution we provided here → https://www.8theme.com/topic/woocommerce-waitlist-incompatibility-for-single-products-part-2/#post-344356 but we had to modify it for you in next way → https://prnt.sc/xp7lt_9NjA7E because it seems one of you plugins rewrites global $product variable with product name → https://prnt.sc/qJ6-Kf1vWGv2 → https://prnt.sc/kAVJPkhL6Jpo that is a very and very not good idea for them.
Waiting for your reply on our solution btw!
Kind Regards,
8theme team