In that case - I'd say it could be modosophont, really. Maybe low transapient, but that needn't be the case. The description of it doesn't really indicate a particularly high level of intelligence, just a rather strange way of communicating. The abilities described could probably be mainly managed by modosophont tech or certainly low transapientech. It might be a construct or tool rather than a sophont being in its own right.
EDIT: One thing that wouldn't really work in OA is the very rapid growth rate and ability to apparently grab resources from the local environment no matter what it consists of. OA tech could pull resources from the local environment, but it would need to contain sufficient quantities of the necessary elements for that to work. If it was mainly made out of carbon, putting it in a steel room would stop it from doing much growing. OA tech could make something grow fast, but not as fast as is described here.
Todd
EDIT: One thing that wouldn't really work in OA is the very rapid growth rate and ability to apparently grab resources from the local environment no matter what it consists of. OA tech could pull resources from the local environment, but it would need to contain sufficient quantities of the necessary elements for that to work. If it was mainly made out of carbon, putting it in a steel room would stop it from doing much growing. OA tech could make something grow fast, but not as fast as is described here.
Todd