Nail said:
It's possible there was.
For example, it may be the case that the cave penalizes size Large creatures when they use their weapons, rather than penalizing Large (3.0e) weapons. If that was the case (and we remove the OP-added missile weapon penalty), then the terrain gives the ogre a distinct disadvantage.
I have the adventure and can list some of the conditions of the caves wherein the ogre had his lair. The module gives lists some general qualities of the dungeon level and details specifics for each area.
In general, the rock in these caves is described as being "damp and slick," and unless otherwise noted the height of the tunnels and rooms from floor to ceiling is about 12 feet. This results in the following adjustments:
*Characters who try to run must make a DC 15 Balance check or slip and fall. Characters who fall must roll a d10 - this number is treated as a percent of how far the character moves before falling prone.
*All characters have a -2 to Climb checks.
*All characters who fight with two-handed weapons suffer a -2 penalty to melee attack rolls.
*All characters have a -2 penalty to Listen checks (due to the incessant sound of loudly dripping water)
The lair of the ogre is indeed the only way into the dungeon. The entrance is about 20 feet across, leading into the southwest end of a room that's roughly trapezoidal. The length of the room is about 50 feet. The eastern wall of the room is about 20 feet long. The western wall of the room is about 40 feet long. There is a single exit, a corridor 10 feet across leading out through the center of the north wall. Because the area description doesn't specify otherwise, the room is about 12 feet high.
This is the description of the room from the text:
"... The floor is thick with debris, six inches deep of bones, dirt, and loose rocks along the edges of the room. The chamber’s center holds a crudely-dug fire pit, while a thick pile of blankets and furs lies against the eastern wall. An iron spike driven into a crack in the western wall by the cave’s entrance serves as a hook for a lantern."
The ogre, named "Logbrag," is at the eastern end of the room when the encounter starts. Logbrag is delusional, thinking the PCs are emissaries of some dark gods sent to bring him to the afterlife. He also has obvious physical deformities, such as glowing green eyes and "rancid, oozing pustules on his back." (in later areas the adventure gets pretty high on the "ick" scale

) However, none of these things hinder the ogres combat effectiveness. After babbling on about denizens of the caves beyond, he "hefts his club with a resigned sigh and attacks, shrieking that the gods will not have his soul without a fight."
The ogre's stat block is listed below (it's correctly identified as CR 3 - EDIT: I have the "updated to 3.5 version"):
Logbrag the Ogre: CR 3; Large Giant; HD 4d8+11; hp
29; Init -1; Spd 30 ft.; AC 16, touch 8, flat-footed 16; Base
Atk +3; Grp +12; Atk/Full Atk huge greatclub +8 melee
(2d8+7); Space/Reach 10 ft./10 ft.; SQ Darkvision 60 ft.,
low-light vision; AL CE; SV Fort +6, Ref +0, Will +1; Str
21, Dex 8, Con 15, Int 6, Wis 10, Cha 7.
Skills and Feats: Climb +5, Listen +2, Spot +2. Feats:
Toughness, Weapon Focus (greatclub).
Possessions: Greatclub, hide armor.
So there you have it. FWIW, I would run this encounter differently from how the text suggests it should go down. First, I would have given PCs the option of possibly convincing it to leave them alone (according to the text, the ogre is obviously meant to reveal certain aspects of the dungeon and then fight to the death). If that fails, I wouldn't have had the ogre to wear it's armor (after all, how can PCs see all the pustules on its back if the ogre has it's armor on?). At the very least, I would have given the ogre a penalty to attack rolls and have it act rashly because of its great size and its delusions. If it charges (and I probably would have made it do so), I would have forced it to make a Balance check to see if it falls or not (although I think I can forgive DMs who forget to enforce the DC 15 Balance check for the monsters - the encounter write-up doesn't mention it and it's easy to forget). If I can fault the encounter for one thing, it's that it doesn't mention how difficult this encounter could be for a group of 1st level PCs.