Soooo, what with using Loyalty instead of Charisma, and Connection instead of Negotiation, why wouldn't everyone just get Connection 6 contacts? As far as I can tell, you can improve Loyalty, but not Connection, right? Presuming the formula for the various legwork activities remains unmodified except for skill and attribute substitutions, you'd use the following:
Legwork extended test (required if we don't know what knowledge skill ratings the contacts have): Connection (Negotiation) + Loyalty (Charisma)
Networking: Etiquette (what do we use for Etiquette, by the way?) + Loyalty (Charisma) + Connection
Swag: Connection (Negotiation) + Loyalty (Charisma) + Connection
With a C6 contact, getting gear becomes a 6+1+6 test, and as I understand it you HAVE to buy hits. Since you round down, that puts the maximum avail you can get at 12 until you get a C7/L2 (easiest approach, alternatively C6/L4, or C5/L6) contact, at which point you can get avail 14 items. Is this really as intended? This does throw a bit of a spanner in the wrench for cybered street sams, as a lot of the implant weapons start at avail 12 and become avail 14 if you use alpha grade limbs, which seems like an unfair disadvantage to me.
And finally, if we don't know the values of their active skills (negotiation and etiquette specifically), do we know their values for knowledge skills? If not, that makes them all pretty useless for legwork...
The way I see it, you've got to be able to use the sample contacts from the Core SR5 rulebook with skill values as-is, with the possible exception of using Connection and Loyalty instead of Negotiation and Charisma.