A bit hard to follow, but it seems like things are working as intended.
CATALOGUE_ENTRY_FIELD_VALUE looks up a specific entry based on entry ID.
You mentioned you have a custom field. Custom fields for a content entry are themselves stored in a catalogue entry.
You mentioned the custom field references another catalogue entry.
It sounds like you are getting confused between having a video referencing a catalogue entry which itself references another catalogue entry.
When you said {$CATALOGUE_ENTRY_FIELD_VALUE,{$GET,bound_catalogue_entry}} works but for a single field -- well, you didn't include a field sequence number. The field sequence number defaults to 0, which is the first. {$CATALOGUE_ENTRY_FIELD_VALUE,{$GET,bound_catalogue_entry},1} Would be the 2nd custom field of the catalogue.
If you want to get the raw value of the 1st custom field and then reference the catalogue entry that field is pointing to to get the title field (1st field) of that entry, I think that would be...
As for PARAM_INFO, that only returns parameters to a template. The custom fields are not themselves parameters because they have to be looked up individually as described here.
CATALOGUE_ENTRY_FIELD_VALUE looks up a specific entry based on entry ID.
You mentioned you have a custom field. Custom fields for a content entry are themselves stored in a catalogue entry.
You mentioned the custom field references another catalogue entry.
It sounds like you are getting confused between having a video referencing a catalogue entry which itself references another catalogue entry.
When you said {$CATALOGUE_ENTRY_FIELD_VALUE,{$GET,bound_catalogue_entry}} works but for a single field -- well, you didn't include a field sequence number. The field sequence number defaults to 0, which is the first. {$CATALOGUE_ENTRY_FIELD_VALUE,{$GET,bound_catalogue_entry},1} Would be the 2nd custom field of the catalogue.
If you want to get the raw value of the 1st custom field and then reference the catalogue entry that field is pointing to to get the title field (1st field) of that entry, I think that would be...
{$CATALOGUE_ENTRY_FIELD_VALUE_PLAIN,{$CATALOGUE_ENTRY_FIELD_VALUE_PLAIN,{$GET,bound_catalogue_entry},0},0}
As for PARAM_INFO, that only returns parameters to a template. The custom fields are not themselves parameters because they have to be looked up individually as described here.