I have the same RF taperlock bb and the cups are marked exactly the same as yours and fitted into my bb shell no problem, though they were a little stiff going in due to the thread lock on the cups.
I'm pretty sure RF only made an English threaded version of this so it makes me think there might be something going on with your bb shell.
nothing to do with the thread lock. are you sure they are marked EXACTLY the same? now knowing what's wrong, the arrows clearly indicate which way it should thread into the frame BB shell. they should be OPPOSITE directions as RH is Right Hand thread for the non-drive and LH should be Left Hand thread for the drive side. it is confusing as i thought RH on the one cup meant Right Hand side of the BB when i first got it, but clearly it is NOT the case.
as people have stated, it looks to be two different cup revisions of the non drive Right Hand thread i've been given.
and as stated, both cups thread into the non-drive side. as well i tried TWO other BBs to be sure it wasn't a bb shell threading issue. a Shimano UN72 and a MRC Ti BB and both work fine. both weren't the axle lengths needed for the crankset i wanted to use.
seller is giving me grief now as i told him about the issue and given him the picture. he's suggesting i may have swapped the cups as the colour shades are a little off. but that prob stems from his impatience with me due to complaints about the transaction i made prior to finding the issue with the BB. i had brought up the issues to see if he'd be willing to do something for me, but i had not demanded anything. just cuz i complained he's fed up with me.