The short answer is no, you can't directly call a Bot thru REST right now. But, if you've got access to NWC we can make it work
Basically, you can use a REST call to start a 1 action Workflow. In the Workflow, you'd have DocGen to create an Excel file with the info required, with the output placed into a cloud drive, like OneDrive or Google Drive. Foxtrot can monitor a folder for this file, then open & scrape the data to preform the steps needed. After that is done, then you can setup the REST POST call in Foxtrot to return to the original system.
Let me know if I should clarify anything!
If I may pitch in here - I would consider just sending an email from NWC to an email inbox that a Foxtrot is monitoring (or an Outlook that then generates a file like in this article https://support.foxtrotalliance.com/hc/en-us/articles/360018207251). With email, you can both include data inside the message body and attach files that Foxtrot can grab for further processing.