In windows we can try to open a pdf with an pdf with VLC or such type of operation. In short "open with" option works more freely in windows than in android. Sometimes because of this even, we can not open some files that we know can be opened with available apps. Is there a way to achive this in android?
Try installing Total Commander file manager for Android (from Google Play store) - it's free and has no ads.
Navigate to the given directory, long press on the file, and select the option
Send to */*, then select the application you wish to open the file with.
That's the method I used to send a
.epub to Google Play Books.