Space Coyote said:
...During the fight I kept advising the Wizard player that he sees 'strong' magical auras around the objects...highly magical
I think you did GREAT except for this part:
"Strong" magic has a very specific game meaning of a 7th-9th level spell or 12th-20th caster level for items. That's pretty powerful for Dispel Magic.
The clue should have been "faint" magic - that's 3rd or lower spell level or 5th or lower caster level for an item. Better yet, you should have said "very faint" - which is not a game term, but would have been a really good clue to try Dispel Magic.
Also, "faintly magical" rather than "highly magical" might have enouraged an attempt at Dispel Magic as well.
You might have also described this effect as being very unusual, not a thing he's heard of in his magical research in the past. That might have triggered him to try something unusual, like Dispel Magic - which is not really the normal answer in this scenario with mutiple objects each with it's own aura.
Unfortunately, you actually (unknowingly) DISCOURAGED the use of Dispel Magic as your clues seemed to indicate it would have little chance of working and, even then, would only probably affect one of the objects temporarily - remember that you described each object as having it's own aura. The caster level of a 7th level spell is 13th level, meaning the DC would be at least 24 (or 23 for caster level 12 item) , not an easy one to beat unless this is a fairly high level party. The way you stressed the strength of the magic, I would have assume a ascter level of more like 15th or hiogher, meaning a DC of 26 or higher, and that's tough for a normal Dispel Magic.
Some sort of Anti-Magic effect (like "Antimagic Field"), however, if available, should have been an obvious choice as that generally ignores the power of the magic.