IOMMU and Internet Connectivity via Hotspot

[SK777]

My only Internet access is through a cellphone hotspot. Works fine as long as IOMMU is disable but from what I read it is best enabled for Qubes and security??? When enabled, I can see the hotspot but when I try to connect and being prompted for the password, it doesn't connect, it repeatedly asks for the password. If I reboot into Qubes with IOMMU disabled, password is accepted and I can connect. At least with Qubes R3.2. Now that I'm using Qubes R4.0 I want to use Qubes properly and configured with the correct settings and proper practice. I have a fresh install and don't want to turn IOMMU off to get Internet if unsecure or possibly compromise my Qubes R4.0 install.

So is it true that I want IOMMU enabled for best security?
How can I connect to the mobile Hotspot?

I really want to transition to using Qubes full time the correct way not the lazy way of just because it works it is fine.

Thanks,