I believe the combine has a required Research skill on it to make the engraved rune, what's your research skill at?
oh ok didnt know that... my bad... my research is at 54... Any chance you know the exact skill level needed?
Straight from Allakhazam, so take it with a grain of salt. Engraved Rune (Research, 15 trivial, No-Fail Combine, Minimum Skill Required 200)
Also from Alla - sort of illustrating my point above. - You'll need a caster with a Spell Research Kit (no skill required - container must hold at least four items).
Ok I went into Ikkinz 2 and took all the mats to POK and tried combining it every 5 points of skill i got in research and i succeeded at 100 research on both items.
Ikkinz 2 research combine is 100 trivial, 100 min skill (http://projecteq.net/edit/index.php?editor=tradeskill&ts=58&rec=10355) Ikkinz 4 research combine is 200 trivial, 200 min skill (http://projecteq.net/edit/index.php?editor=tradeskill&ts=58&rec=10896)