Recognise this one could be a big ask but it's worth recording to see if there's demand.

gopacket/gopacket#1 seems to have added support for the cooked mode packet captures that tcpdump (in any interface mode) and termcap.

Unfortunately the dumps already exist, so it's going to be a tcprewrite job to convert them to ethernet framed pcap if support isn't possible or feasible.

Edit: Just realised it's merged into a fork of the google gopacket library, not the upstream... :(
google/gopacket#933

That said google/gopacket#1016 seems relevant to the above points.