You can avoid TT255 by exiting the bridge area and turning right on Hwy1472. Either way, you still go around both Laredos and I think that is the beauty of the bridge.
After turning in your TIP at the caseta, you go continue ahead until you find the left turn lane. This left turn lane is a constant loop that will take you around and around. Let's say you miss the caseta for the TIP, no issue. Go ahead and take the turn around. After, take the turn around again and turn in your FMM.
All of this can be seen by doing a Google Earth search. It shows quite clearly the immigration buildings as well as the loop turn around, the crossing into the U.S. and Hwy 1472.
You never enter either city by using this crossing. That said, we had issues using Bridge #2 this last week. Heading to San Antonio last week we were not treated very well by U.S. immigration during the TT inspection and the unusually strict interrogation. Coming back through Bridge #2, ICE agents shook us down. I won't go any further but the Colombia Bridge is the best option IMHO.