I am currently using RX 5.. I was at a field recording workshop last week, and someone did an RX 7 demonstration. I am unsure if I can do what they were doing with my version, but they somehow created a fade out, and a fade in, and removed the unwanted section of audio between them creating a seamless transition. I know they used equal power fades, and reduced feathering to 0 (I cannot find the feathering option in 5), and I think they somehow copied the fade out and overlaid it over the fade in, or something like that. I hope this makes some sense... I cannot figure out how to do it. Any help would be appreciated!
This kind of audio editing is relatively painless with a modern DAW (digital audio workstation), everything from Reaper to Samplitude to Pyramix all make this kind of editing easy. Even the audio packages that come with NLE (non-linear editing) software like DiVinci Resolve and the Adobe suite can do this.
That said, the iZotope RX family is highly regarded and aimed at doing audio repairs. One would think this kind of repair is exactly what they do. So I'm relatively sure your downlevel version should do this also.
As to how it's done in your software and your version, I have no clue. I've never needed what iZotope has so I've never used it. But if you google around for a tutorial I'm sure you'll find step-by-step instructions out there somewhere.