See the minor edit to my last post.
I know exactly what you mean!
Temporarily terminate your Cat5e wit a plug or socket. Get the Modem installed at the Master location and use the Cat5e to feed the WAN connection to your patch panel and then to the Router.
Then make legitimate changes yourself.
The full VDSL master socket is in four parts: Back Box, Master Socket termination (top half); VDSL filter which is full length but with the top half protruding and bottom set back and unfiltered output in the top; and finally Voice connection lower half.
Using a suitable pair from your Cat5e cable, connect to the IDC pair on the VDSL filter plate - top left, then with another pair, connect to 2 and 5 on the voice plate IDC and possibly a single one of a pair to 3 (ring wire - may be better without, provided your phones are able to ring without it).
At the patch panel break out the VDSL and voice signals.
M H C
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