In my Commercial practice we've ALWAYS been required to run a bonding conductor over to the telco board which by contract we also installed. Said board would ALWAYS be a hefty 4x8 sheet of plywood treated for fire resistance -- sometimes plain, sometimes painted ( by the GC/painting contractor ) at least 5/8" thick.
The Telco tech was ALWAYS very good at grounding at their Point Of Entry.
Providing raceways all over for the LV boys and pulling in phone pairs for the elevator contractor... all in a job.
------
Plainly, Residential sequencing is totally different. It sounds like you're long gone before the LV crowd shows up.
