As one of the options, the Bash manual offers using `Meta-/` to specifically complete filenames. 

> **8.4.6 Letting Readline Type For You**
>
> ...
>
> **complete-filename (M-/)**
>
> Attempt filename completion on the text before point.
>
>

`Meta` is usually `option` on Macs (check if it is enabled in Terminal) or `Alt` on PCs.