True that Ice would be trapped .... but again using the trailer as 'evidence' of structure composition .... couldn't the surrounding 'trees' and the central core be a kind of Thargoid mining operation.... drilling into the ice to tap into netrient sources or even down to liquid water which might have amino acids/proteins
Theres one Icy body (many volatiles) with CO2 Geyser volcanism. If theres an active geological setup could that provide a stream of volatiles? I *may* need more coffee.