Do you need a Multipass of your own? I worked to make the best model that I could and you can get it here - https://www.prusaprinters.org/prints/67610-vaccination-multipass-holder
I took the design and made some adjustments to the geometry and finish to allow for a standard US CDC sized Vaccination card to rest in. The original badge holder hole is now being used as a locking stop with a part I made to slip on over the top after you have placed your card inside. There is room for your card and a piece of thin sheet plastic (you can use a recycled food container or any sheet plastic cut to size). If your Vaccine card has been laminated it should also fit (Note: make sure to trim the lamination to fit).
For bonding the top and bottom half it is recommended to use superglue or 5 min epoxy. I really like the 5 min epoxy as it added more strength to the parts which are pretty thin so its not so bulky. The end clip is a press fit and you may want to print extras (I included two versions to accommodate laminated cards).
*I also added a great reference image from the replica prop forums on the components that make up a multipass if you need it for reference.
Printing Notes:
You should need no supports for any of the files.
I recommend rafts for the end clips it keeps them steady and adhered to the build plate.
Lower temps on the bed help with deformation on the build parts after the first layer.
Recommend 60C for the first layer and then drop to 50C
Be safe, get vaccinated, and don't forget to wear a mask even after you have your Multipass filled out!
Check out the original model I used to base my design on the wonderful Convention badge holder by Jurgizmo that I definitely recommend you check out! - https://www.thingiverse.com/thing:491108