Using a Wildcard to Specify Source File in Batch File

I have a scenario where I do not/will not know the file name of the file I’m wanting to split. I only know part of the file name. I have created a batch file that specifies the source directory and a wildcard, e.g. c:\gsplit\sometext*.txt. when I run the batch file from the command line, I get an error indicating
“Fatal Error” “The original file “c:\gsplit\sometext*.txt” was not found”. Is there anyway to use a wildcard to identify the source file name?

Better use some Python script to get a list of all files and pass them to GSplit one by one.