Bad guy/malingerer is unlikely to gain a reputation for reliability; Garth's poorly disguised excuses, however, were improbably interpreted by his fearfulness/ trepid, hypochondriac employer as a sign of great foresight and sagacity.

Embezzler and Pilferer is related to stealing/fraudulently use someone's property. So, malinger fits in.Garth's poorly disguised excuses, however, were improbably interpreted by his fearful/trepidadious and hypochondriac employer as a sign of great foresight and sagacity (fits well with great foresight/wisdom).

SPELLING MISTAKES!

(D) should be CAUSTIC, not causistic
(F) should be TREPIDATIOUS, not trepidadious
(G) should be INSIPIDITY, not insidipity

That said, I don't understand how the excuses could be seen as a "sign of great foresight and sagacity." I mean, excuses are excuses. How can they make a person look like he is sagacious and has great foresight? The sentence doesn't really make sense to me.

Fixed the typos.

As for the second blank is casuistic = practicing clever but unsound reasoning a sort of random fortune.

Honestly, this is a question far from the quality and charm of an official question, even though is a question from Manhattan GRE.

Stuffing a sentence with difficult words does not mean it is a good question from which you learn something really useful.

Thanks
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