Answer: Wow! Your question is a real stumper! Let's begin by vindicating the peppers and the armadillo. Peppers won't "taint" the soil and armadilloes will dig small holes looking for grubs and other such food but won't cause "dried up" plants. You should contact your County Extension Office for information on soil testing. Some nurseries also offer the service.
Possible causes of very rapid drying and death of plants include: root feeding pests (carefully dig up a plant and look for severed roots), root rots (shows up as brown to grey, watersoaked roots and/or base of the stem), fertilizer burn (caused by overapplication of a salt based commercial fertilizer or placing fertilizer in the planting hole), or chemical burn (some pesticides, including insecticidal soap, can burn plant if mixed too strong).
I would have my soil tested as a general guide for future nutritional needs. If the above examinations yield no culprits, try replanting too see if the problem has corrected itself. They often do!
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