The HE link doesnt mean they are signed. It just means the IRR records are correct. You would see a green key on the prefixes if they were signed (and correct)

The prefixes are in the https://www.radb.net

Somebody (as everybody can do this with radb) said to RADB that 8003 is the correct origin for these prefixes.

Considering the DoD hasnt rained hell on the RADB, Id guess theyre good as well, but its not RPKI signed.