You say not to fill with foam, so what do I use that is cost effective? I have one part of a log (2 ft.) that the termites destroyed. The termites are gone. We can’t do a partial log replacement because a rock wall is covering most of the damage. We can replace about 10 inches of the log. I injected Liquid Wood (using a meat injector) into the termited area, then added WoodEpox. Now I have about 12 inches of open space inside the rock wall. What may I use to fill this area?Thank you v