Yeah, I agree. My employer is a supplier to a GM facility and there are several entrances to the plant once one is past the security guard check-point. My particular entrance is at the end of a long(about 200 ft)covered catwalk about 25-30ft wide w/rails. When the weather was warmer I locked my bike to the rails near the door...maybe 25 ft away. When the weather changed I simply found a place inside that was out of the way and started to lock my bike there. Again very close to the door, but off to the side so as not to have the bike be a 'trip-hazzard'. The mistake the OP made was even asking in the first place. Every 'static' job I've had in the last 20 years of cycle commuting I've never 'asked' where I could park my bike inside...I just did it. If there was an issue I was ALWAYS given an INSIDE alternative. Whether it was a janitorial closet or 'low traffic' area.
One employer asked re the bike being wet and I replied I kept a towel at work specifically for the purpose of wiping down my bike in wet weather. That mollified him and I was able to continue to park inside.

A 100 person place of employment is pretty big...I'd scope out the most unobtrusive place in the area and simply begin to park my bike there w/o even mentioning it. Everyone will assume permission has been granted and probably not even question it being there.

Sometimes, in trying to 'do things in the socially acceptable manner' one ends up screwing oneself. It's better to be assertive bordering on insubordination when trying to find suitable indoor storage for one's bike in the workplace. When one calls attention to the situation it gives management or security an opportunity to say 'No'. Which they will do in most cases simply because they can. That's been MY experience, anyway.