looks like they have been undone.
no way the tops would 'pop' any other way.
check the internal thread of the fork, bet it's fine.
FYI i have a complete front end lying about (forks, yokes, wheel and mudguard (silver)) which i might part with for money.
used to have an 1100S myself (chipped,laser cans, Y piece, GS torque arm, BCR suspension, Schnitzer rearsets, lennies)