And most peoples home network wont be able to support VLAN's and would your employer be more worried about your ISP provided router - hmm must really replace that huawei router on my network.
I think it would be reasonable to ask for a separate internet connection and router myself. If someone wants me to install opaque software that can do whatever it wants in terms of outbound/inbound packets, then they should be okay paying for it to be completely separate.
Interesting though my network is powerline so id need one in front of every POE switch (and that's assuming the powerline devices would pass the Vlan tags)
And id need a VDSL Router that supported Vlans as well so that's 4 switch's plus a router.
https://www.newegg.com/netgear-gs105e/p/N82E16833122598