I'll share some information about the split transaction details reports in QuickBooks Online, Roz.

I understand the importance of this feature in the day-to-day transactions of your business. I suggest sending feedback to our product team to let them know how this is useful on your part and improve the product experience. To do so, follow the steps outlined below

1. Select the Gear icon at the top, then Feedback.
2. Enter your comments or product suggestions. Then select Next to submit feedback.

All your suggestions go to our Product Development team which is tracked. Apart from this, you can also track feature requests through the QuickBooks Online Feature Requests website.

Moreover, QuickBooks offers a variety of reports that provide the data you need most for your business. Learn to customize them to ensure you'll get the correct information. I've added this article for your reference: Customize Reports In QuickBooks Online.

Let me know if you have any concerns with split transactions. Remember, the Community is always here to cover all your needs 24/7. Have a great day!

I can share how I figured this out in Quickbooks online. Not sure what you are using. Took me hours!

In August I was able to use a Transaction report list that I could export and show all the details including split payments to contractors. That option is no longer available. 

This morning I was able to use the Check Detail Report under Reports, expenses and vendors. I customized it for year to date, grouped by Name only (to show the vendor/contractor names in alpha), to show Date, Number, Name, Memo/Description, and Amount. This gave me what I needed FINALLY. I was able to save the report for future access. Hope this is helpful. 

This is the answer right here!  Thank you!

In the report "Transactions Detail by Account"

Total by: "Transactions"

Sorted by: "Default"

Most recently QuickBook Desktop