Using 1st order ambisonics in Atmos - no height channels

Got a strange thing happening - I’m using 1st order ambisonics wav, converted to 7.1.4 using Rode’s Soundfield plugin. Routing direct to the atmos renderer as a 7.1.4 object (12 objects in reality). The soundfield plugin is showing all 4 height channels as active in it’s own gui, but I’m not getting anything in the renderer height channels. This is using the 1st order wav on a 7.1.4 audio track with the plugin on an insert.
If I create a 1st order ambi track and assign it to the renderer the ambidecoder says it’s 1st order > 7.1.4 but the adm authoring panel doesn’t see it as an available input, it;s not in the dropdown list, however, if I create a 7.1.4 group, assign the same track to the group then assign the 7.1.4 group to the renderer as objects it works as expected, but then I can’t use the soundfield plugin controls to adjust anything, rotate etc…it’s like the plugin is bypassed even though it’s on the insert, and it shows no levels in it’s gui.
Is there something I’m missing? I would have thought there would be a simple way to have the plugin convert the ambisonic to 7.1.4 then assign it to the renderer as objects, but it seems not…or I can’t work it out…