Dual sided uFL connections
You could try it, and it might work... or it might not. In general, vias on feedlines are frowned upon because their impedance is hard to predict and will vary due to through-hole plating thickness.
Typically every RF device and trace is built for a characteristic impedance. The moment you connect two uFL connectors to a third trace, you're implying that three devices will be connected, in essentially a &quot;star&quot; topology, which would likely skew the impedance right out of the operable range. It should work with only two devices connected, however, provided that trace is short. Still, adding the second uFL is adding inductance and capacitance to the feedline, which can alter it's performance.
It might be possible to get around this by painstakingly tuning each leg using tons of math, inductors, and capacitors, but this would require a Vector Network Analyzer or similar and prototyping revisions.
Also remember that a trace will start to behave as an antenna when it's length approaches 1/10th the wavelength. I can't tell how long that feedline is, but at 2.4GHz, the wavelength is about 125mm. So a 13mm long feedline at this frequency starts to become problematic (an &quot;unintentional radiator.&quot;) Incidentally, 1/4 wavelength (31.25mm) would function very well as an antenna.
If the device / antenna comes with a suggested layout, it is highly recommended to stick to that.  Anything else is a gamble, and may require re-working and re-spinning the board.