I feel your pain. I had this exact nightmare last year when I was coordinating a robotics build for a summer camp. I spent hours getting the quantities and specific vendors right for about 60 different sensors, only to realize Amazon doesn't have a native send cart button. It is super annoying because sharing your login is a huge security risk. Honestly, your best bet is using a tool because Amazon just wont give us that feature. Here is what I usually do:

• use the Share-A-Cart browser extension. It creates a code the treasurer enters on their end to pull in everything.
• if you have a business account, use the Manage Your Team feature to add them as a purchaser.
• as a last resort, just print the cart to PDF so they have the visual proof. I personally recommend the extension. It handles the quantities and different sellers way better than the wish list feature ever did... it is just more reliable. It really depends on if your treasurer is willing to install a plugin, but it is the most solid way I've found.

To add to the point above: I have been wrestling with this exact same issue for my lab's quarterly procurement and honestly it's exhausting. I'm trying to bundle about 35 SKUs including specific microcontroller variants where the tolerance specs are super critical. Every time I try to find a workaround for the empty cart URL issue, I hit a dead end. I've been trying to solve this for weeks because we need to track the exact unit costs and shipping lead times for our grant reporting, but the platform just doesn't seem to support session-based cart sharing. I have to disagree with the idea that there's some hidden button we're just missing; I've audited the entire UI and checked the dev console for persistent cart IDs. It's frustrating that such a basic B2B requirement is so difficult to manage. Im still stuck in the same loop, basically just hopin for a fix.

OMG I totally agree with the first reply, it is such a massive headache when you are on a deadline!! I have been through this exact thing with my own projects and it is just the worst feeling when you think you are done and then realize the link is dead. The technical reason it fails is basically that Amazon stores your cart in your specific browser cookies and session data, so that URL is only local to your login. It is honestly so annoying but there is a fantastic way around it! You should check out a browser extension called Share-A-Cart because it is actually amazing for this. It generates a little code that the treasurer can plug in on their end to pull in every single item you picked, quantities and all! It is such a lifesaver. Just to be safe tho, since you are dealing with club funds, maybe send a PDF printout of the cart too? That way there is zero confusion on the final price and you have a backup. Good luck to the team in Chicago, I love seeing people get into Science Olympiad!!