As you can see these aren't the familiar glass cased vital relays that would be both costly and time consuming to replace. Instead these are non-vital elevator/telephone type relays used in the CTC control elements. Without any damage to the real interlocking local control can be used if necessary and from the service advisory delays of only 5-10 minutes were encountered at the time of the incident.
Not sure if MNRR is going to try to restore the same functionality or just use some infinitely more simple form of modern technology. The latter would seem obvious, but since it would probably require a brand new custom interface between the non-vital and vital elements I suspect they'll just bring it back exactly as it was. Note the worker with the old wet dry vac already putting a "restore" plan back into place.
MNRR didn't stop at photos, they also produced a video outlining their little whoopsie.
Anyway, fires happen all the time, but few are so well documented in a way that can shine a light on the inner workings of modern(ish) interlockings. Which reminds me...if you travel the New Haven line late at night instead of looking to the south side of the tracks where the fire was, look to the north because inside the tower a single bulb still burns illuminating the original interlocking machine which fortunately did not burst into flame during its 60 years of operation.