How about using plaster of paris ? I have used it on ceramic statues and works well. Not sure how good on plastic.. Maybe use an etch primer first to help it adhere.

You have my sympathy if your wife can prevail where a balrog failed…

Aliphatic glue works well on similarly constructed meerkats (long story…) but it's too late now.

Expanding polyurethane will work as long as you keep it vented, as it's very liquid when first introduced.

Neil

G26 two part resin.

Chuck it away n get a noo one

Once it's back together and smoothed up, make a sand mould and cast a second one in aluminum! No more delicate resin.

Only half kidding, you could do a wood form box and make a plaster mould or a wax mould (one time use) and cast a new G in concrete or urethane casting resin. A "core" of capped plumbing pipe held in the mould could be used to reduce material amount needed.

The foam might well burst it apart. Don't try to fill it 100%. Do like clay statues and chocolate bunnies. Pour a limited amount of resin or some such in, swill it around and pour the rest out (into some other mould). Allow to dry and maybe repeat but only to build up a thinnish layer inside, not a completer fill.

Baby Jesus in our nativity set has his left foot replaced with an epoxy putty prosthetic. Similar surgery restored one of the angels to flight-ready status.

Neil