Your problem may be more than just bellows draw (or compression, in ths case.) I have an old (circa 1970) 35mm Schneider Componon enlarging lens which I bought to print half-frame 35mm negatives (18x24mm). It does a fine job at that, but doesn't have much more covering power - certainly not enough to do a full frame 35mm negative. Traditionally, a 50mm enlarging lens was needed for full frame coverage, although I understand that there are 40mm lenses made today which will do the job. But I would be astonished if there were a 30mm lens which would cover 35mm full frame, and if it were an older formulation it might not even cover 35mm half-frame. I'm not sure what format a 30mm lens might be made to cover - it sounds a bit long for Minox negatives, and I don't know what there is between that and half-frame 35mm unless it is something like 16mm movie film.(posted 9448 days ago)So, even if you could get your 30mm lens close enough to the negative to focus, I'd be surprised if it could enlarge any but the center of the negative. You might be able to confirm this by mounting the lens upside down on the lensboard, if you can mount the lens this way (I have a Beseler enlarger, so don't know details of an Omega lens mounting system). This will put the lens closer to the negative, and might let you focus enough to see what kind of coverage the lens has. Of course you can't use the lens this way very conveniently, but if there is enough coverage for some purpose you might be able to find a recessed lens board for the Omega that will move the lens closer to the negative. I have to use one of these on my Beseler for both 35mm and 50mm lenses. But, at least for Beseler, these are not cheap items, so if I were you I'd try to check the lens coverage first before buying a recessed board.
Hope this helps.
Cheers, Kip Babington