It seems that your LVDS lines are quite close to those vias. Additionally it is not clear how long they are from source to load. I explain why.
From a book on RF measurements & pcb design I wrote a few years ago, a common estimate of via parasitic capacitance is from the snapshot below.
Self capacitance for vias located on the line traces is larger than coupled capacitance for vias next to the line (of course). Note that you have 5 vias, so capacitive loading is 5 time larger, and that the distance from LVDS traces is small (less than 1 via diameter), so coupling is not negligible. As a rule of thumb mutual capacitance may be in the order of 1/3 - 1/5 of self capacitance: to calculate it more accurately...
The effects of capacitance for step-like and pulse-like signals are:
- reduced impedance terminating the line during waveform edges; lower characteristic impedance values give a more comfortable limit of tolerated stray capacitance: an overall 1pF of capacitive loading on a Zc=50ohm line gives 100 ps limit; this means that a 0.2 ns LVDS may slip into troubles if Zc goes up to 100 ohm, as it is ...
- capacitive loading of line sections causes additional delay for signal propagation; this creates ringing during transitions and depending on line length there may be just an "echo" or a nasty superposition; the added delay is 2.2 time constants, that is 2.2 Cp Zc; for common values it amounts roughly to the rise time.
- for a differential line as LVDS is, separation of vias similar to gap between traces causes common-to-differential mode transformation, so immunity of your LVDS is a bit challenged.
I see that the two LVDS lines are not loaded in the same way.
If ADC thermal vias can be blind and finish at some first ground plane inner layer, than LVDS traces in a lower layer will see only the void of dielectric material, that is much better than being sided by vias going top to bottom.
Ref : H.W. Johnson and M. Graham, High-Speed Digital Design - A Handbook of Black Magic, Prentice Hall, Englewood Cliffs, New Jersey, 1988.