It looks like the original question has been answered, but this should've been the correct syntax for the filtering:
[[!pdoUsers?
&tpl=`userListTpl`
&where=`{"modUserProfile.fax:=":"0000000000",
"AND:modUserProfile.comment:=":"Member",
"OR:modUserProfile.zip:IN":["83206", "83209", "83201"]}`
&limit=`0`
&useExtended=`1`]]
The reason the original didn't work is because you're setting array keys and values, and it had the same array key ("OR:modUserProfile.zip:IN") for three of the conditions.