G. excelsa grows in solitary rosettes. So thats out. I've been looking at G. brachyphylla. It looks right other than mine has more than a pair of side branches on the inflo. I need to go feel the leaves to see if there sandpapery.
Checked the feel of the leaves. The mature plant has smooth surface and the suckers are rough. I see that the form can be a rosette with age in this genus. Need to measure a few parts and have a look under magnification.