Hi Ellie:

Thank you for bringing this to our attention! You're right that there's a problem with Rlabkey and E-5 numbers. In my experimentation, there may also be precision issues with E-2, E-3, and E-4 numbers. I've opened an internal issue to track this:
https://www.labkey.org/home/Developer/issues/issues-details.view?issueId=51160

In the meantime, if you're able to adjust your scripts to not use this notation, that's likely the quickest workaround.

--Molly