Can I delete these?

Thank you! I have two main photo drives and always use the newest catalog. As far as my insurance policy goes, every single drive I have, whether photo or video, gets backed up to an identical SSD Drive. I also have a pro 10 TB HDD that I'm backing everything up to as well. Oh yeah, and then there's Backblaze and Google's standard business suite.

A long time ago, I learned a lesson the hard way. All my Photography gear got stolen (15k+). I was going to be without a camera or computer for a while, so I got an iPad and the keyboard and worked on that for years until I got back into Photography. When I finally did get a new computer, I had only made a one-time machine backup. It was 10 years worth of my photography, writing, etc., 10 years later when I finally got a computer again. I plugged the Lacey Porsche HDD drive in, and there was nothing! I was so sad because there were photos on there of friends who have long since passed, etc. However, there is a happy ending to this story about a month ago. I found that drive again and I said it on my desk and one night before bed something told me to use, a USB-C connection I plugged the drive-in and bam. Everything was there, and I pulled all the stuff out! It's so funny. I remember I used to get stressed out about how big the raw files were for my D300. Today I made a focused act Photo of a Douglas Iris that was over 38 GB once it was done crazy time changes. However, I'm getting sick of having 14 2 TB SSD drives lying all over my desk, and I think it's time that I grow up and build some raid system

"Is it safe...?"- It depends. If Z9-13.3-3 is the catalog you are using with all your photos and editing, AND you have been making regular 'Backups' of the LrC catalog (to another drive!), then- Yes. You can delete 'old' versions of the catalog.