If you have room to either add or replace 10" of straight track you could substitute some of these: FasTrack Transition Piece SKU: 6-12040 . The traditional O Gauge round pins on one end of these transition pieces are easier (in my opinion) to join and disconnect than standard FasTrack connectors. If needed, you could also use some type of cam lock (think Window latch) to cinch up the connection. I know there's a more robust type of cam latch used for securing sections of modular layouts together, but I don't recall at the moment what they're called or where to find them. Window latches or simple draw latches may work well enough if secured through the foam board into something solid underneath.
4x 
+ 2x 
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