This is infuriating, because I already put together a whole reply regarding the outputs of the last run, and it doesn't seem to have posted. I'm not entirely sure how best to do this, but I'll repeat what I did a few minutes ago. (This goes right along with the day that I've had trying to get this to work.)
I can see that it's stepping through the three files:

The file names are right and there are truly three of them. They have a person's name in the file name, so I'm not including them, so that I don't have to black that out on each of them.
Next, we have...

However, it does look different on the second and third files. I don't know how to read this, but here's the second. I've removed the millions of random characters after "$content" and just replaced with ellipses...
{"statusCode":200,"headers":{"Transfer-Encoding":"chunked","X-SharePointHealthScore":"1","X-MS-SPConnector":"1","X-SP-SERVERSTATE":"ReadOnly=0","DATASERVICEVERSION":"3.0","X-Download-Options":"noopen","SPClientServiceRequestDuration":"78","SPRequestGuid":"b5ef020d-5db4-41c7-98d9-5ba4425ceb58","request-id":"b5ef020d-5db4-41c7-98d9-5ba4425ceb58","MS-CV":"DQLvtbRdx0GY2VukQlzrWA.0","Strict-Transport-Security":"max-age=31536000","X-FRAME-OPTIONS":"SAMEORIGIN","MicrosoftSharePointTeamServices":"16.0.0.20015","X-Content-Type-Options":"nosniff","X-MS-InvokeApp":"1; RequireReadOnly","Timing-Allow-Origin":"*","x-ms-apihub-cached-response":"true","Cache-Control":"max-age=0, private","Date":"Tue, 28 Apr 2020 22:53:27 GMT","P3P":"CP=\"ALL IND DSP COR ADM CONo CUR CUSo IVAo IVDo PSA PSD TAI TELo OUR SAMo CNT COM INT NAV ONL PHY PRE PUR UNI\"","X-AspNet-Version":"4.0.30319","X-Powered-By":"ASP.NET","Content-Disposition":"attachment","Content-Type":"application/pdf","Expires":"Mon, 13 Apr 2020 22:53:28 GMT","Last-Modified":"Tue, 28 Apr 2020 22:53:28 GMT","Content-Length":"589673"},"body":{"$content-type":"application/pdf","$content":"JVB...DQo="}}
And, then, the variable inputs:
{"name":"Files","value":{"fileName":"blah.pdf","fileContent":"JVB...DQo="}}