I was having some similar errors about memory allocation that others had posted.
- Add basic product info
- Add variations
- Page is slow to load and getting memory errors
- Product is missing, but the product count for category increases on admin side - not client side.
I tried increasing the memory settings in PHP and in wp-config.php, but neither worked.
Since the site was not life I had not configured Yoast's WordPress Analytics plugin and had a small red warning at the top of very admin page.
I configured WordPress Analytics and the problem went away.