How do I connect the cue-note beam at the indicated location?
In the full score, should I re-input the cue notes as a single-bar beam rather than a cross-bar beam?
I don’t think you can connect them because these are two separate cues (you can’t add both staves of a grand staff as one cue AFAIK). To achieve what you want I thing adding a separate cue staff with all the notes in the same staff is indeed the best option.
You can enter the clefs manually with the caret:
Thank. @Zalde @charles_piano