In that case I believe it is a conflict with the tfadmin.fgd you are also using. Didn't occur to me when I noticed it in the errors before. If multiple FGDs have the same entities defined the last one loaded is what gets used. Judging by the error messages tfadmin.fgd is being loaded last, which has it's own inclusion of tf.fgd, which would override what was set by mine.
Without knowing what exactly is in tfadmin, my recommended course of action would be to open tf-abs.fgd, and change the top line to include tfadmin.fgd rather than tf.fgd so that the inclusion order is tf-abs -> tfadmin -> tf (which will then be loaded in reverse, since the includes are at the top and handled first).
After that, remove tfadmin from the list in Hammer and leave just mine in there.
If there is anything that both tfadmin and tf-abs customize, then that won't work and they would need to be manually merged.