Preferred method for adding movies not released outside bundles

[FangsFirst]

Don't think I can find an explicit answer on this, but as a semi-regular participant in a number of other online databases, I want to be sure I'm not going a little too "cowboy" here…

I was just parsing my collection by movie ("Complete" view) and noticed a missing movie (Ultraman Zearth 2). In following up, I discovered that a double feature (the Ultraman Zearth double feature) is linked to only one of two movies.

I decoded I was going to fix this, so I followed enough threads and looked at enough examples to understand that we have to have independent releases to add as bundle IDs (vs. the movie IDs). I saw some recommendations that one should not add a disc release if it was not released as an independent disc(especially if, for example, it was not on a separate disc at all, but all on a single disc, as is the case here).

I've seen others where a "non-existent" single release is created so that a bundle ID is available to add the movie to the bundle release, and I'm not sure if that's a no-no or an acceptable concession.

Seems to me that, given the way the database entries are constructed, this is a desirable concession, else the database misleadingly suggests that there exists no release of Ultraman Zearth 2 on disc when there is one (the double feature in question).

The discussion I ran into on here was using as an example the AMC Classic Dramatic Stories set, which does not reflect the films it contains (outside some comments/notes/descriptions). So anyone with it in their collection would not have a listed ownership of the movies in it, which doesn't seem good to me either.

Is a "fake" release desirable (a disc with few/no specs, or maybe referencing the specs from the bundle, even though it isn't available separately), or is the standard to live with releases that aren't tied to the specific movies? Maybe some alternative I just haven't run into?

Cheers!