If your bandwidth is a only few 100 MHz, then some wiring oddities over a few cm will do no harm. As a rule of thumb, a transmission line discontinuity of 1/20 lambda long is tolerable. From my dim recall of communications theory, 100 Mbits/sec requires a bandwidth of at least 150 MHz. Lamda for 150 MHz is 2m. So a dodgy bit of transmission line no more than 0.1m should be tolerable. Well, yikes! I would never put up with such a mess at VHF. I am sure you can do better.

I should point out here that microwaves101 is dedicated to microwave topics, where interesting things happen at frequencies of many GHz, and physical features of fractions of a millimeter. On my own admission, I do not really belong here, as my RF expertise is in UHF (300 to 1000 MHz), not microwaves. Having said that, microwaves101 has provided many useful guidelines for my designs.

On a more practical note, the answer to the question "will it work?" is to test it. To me, testing means hiring some kit or a lab session to find out whether your non-standard connector affects attenuation, bit error rate, and so on.

If you silver plate to 5 skin depths, then the base conductor properties should have negligible effect on microwaves. Depth of penetration means just that, for magnetic as well as electric fields.

Somewhere on this site, there is an analysis of thin gold over nickel plating, which shows that this is rather bad for microwave losses, as the RF penetrates the gold into the lossy nickel. I am sorry, but I cannot find the page right now. For much thicker silver plating over pretty much any base conductor, then it appears that one can ignore the base conductor for microwave performance.

I note that copper or silver coated steel conductors are often used in fairly high grade coax, to provide additional strength and mechanical stability, without degrading RF losses. The only case I have seen where copper coated steel conductors present a problem is cheap cat5 cable used for power over ethernet (POE), where the DC volt drop is much worse than pure copper conductors.