Adding HPE GPG/RPM signature file to kickstart

I have a rack of DL380 G10 servers with an HPE 621SFP NIC in each. Trying to install with RHEL 7.6, but the standard drivers don't work with that NIC and I have to add the HPE drivers from kmod-qlgc-fastlinq-8.42.8.0-1.rhel7u6.x86_64.rpm (I installed a test system directly from the console using the iso image). The NIC would not work until I added the kernel mode drivers. I had also notices during kickstart, the NIC was able to get an ip via dhcp and pull down the various files (shim.efi, etc) via tftp, but when trying to pull down the ks.cfg over http, that failed. When I added inst.dd=http://1.2.3.4/kmod-qlgc-fastlinq-8.42.8.0-1.rhel7u6x86_64.rpm to the grub.cfg, it did pull the ks.cfg, but then failed. In the rdsosreport I see a couple of lines that suggests it is not going to use the kernel mode drivers from HPE because of unknown module key. I can get HPE's GPG/RPM key from https://downloads.hpe.com/pub/keys/HPE-GPG-Public-Keys.tar.gz, but not sure how to add that to the kickstart configuration? Any suggestions?