It's sounding rather like all you have is the output. In the root of the source you will find XPJ and CPD files amongst others. In the output you will typically see index.htm and that will open the output. A screenshot of that would help to identify whether it is webhelp or a responsive output.
You could look at one of the sample projects to see the different types of file in the source and outputs. Click Open on the RoboHelp Starter page and then click Samples in the ribbon on the left.
Whilst you say you have the ingredients, if they are output files then you don't have the ingredients as whilst the file names are the same, the HTML is very different.
You need to search for the XPJ file to find the source. I'm guessing it is on the PC used by the previous author. Is it still available and still accessible?
If not you have the fun task of reverse engineering the output. See Reverse Engineering on my site if you have to go down that path.
Let us know more first when you have poked around.
See www.grainge.org for free RoboHelp and Authoring information.
First off, thanks for taking the time to reply to my problem; I really appreciate it. The owner of the previous PC had many backups created, and I found out that we may be able to recover them. I've filed a ticket with my IT team to try and recover them, but it's no guarantee they'll be able to recover them. I'll also bookmark your page as a source in case I have to journey down the reverse engineer path, but I'm hoping it doesn't come to that.
Here are two screenshots, the first being the files I have, the other being the index.htm file which is opened up.
Other than reverse engineering the output, any other suggestions?
I'm not Peter, of course, but there are no other options but to reverse engineer if you don't have the source files.