I agree that it's almost certainly going to be underfixing, especially given the colour of the stains.(posted 8151 days ago)
I use Ilford rapid fixer diluted 1:9, as a one-shot fixer for T-max film. But I extend the fixing time to 6 minutes @ 68 F.
I did a few tests before using this dilute rapid-fixer technique, and most films are barely cleared after 2 minutes.
The very short times given in the instructions for fixer these days are marginal anyway, IMHO.