Sean,
The confidence intervals for tau2 and tau are certainly wrong / meaningless.
I could have a closer look if you send me (part of) your data set with
these strange CIs.
Best wishes
Guido
P.S. Internally, meta calls rma.uni() and confint() from R package
metafor to calculate the confidence intervals for tau2 and tau. I do not
assume that there is a problem in the computations in metafor.