This would work although you would be doing it in a roundabout way. The midi bits are really midi to control voltage (cv) converters so you would be converting midi to cv then cv back to midi. One thing to keep in mind is that the gate is transmitted through the trigger out bitsnap. A CV bit could be used connected to the trigger out then sent to the sync input of one Vulca and then chained the other using the sync out.
With all of that being said, it would be an expensive option if you were using it just to split a midi signal. I have the bits and they work great for integrating the bits with my other gear and love the interesting things you can create, but you could get an ordinary midi splitter for the same price as one midi bit.
Highly recommend the bits, but it might be overkill for just a splitter ;D