It looks like a simple fix. Worst case, fuel is trapped in vent line due to ram air pressure. In that scenario you would still have atmospheric pressure through your PCV.Thanks for the description.
When I initially installed the fuel tank, I didn't realize that the vent line went down in front of the landing gear (I reworked it after everything was completed).
I had installed a PCV valve to act as a vent.... that way it would allow suction but prevent fuel from splashing out.
Thinking of reincorporating it into the current system:
View attachment 15047
Normal venting can occur using the drain line - green line but if it ever gets plugged and a suction starts, the PCV would take over and allow air to enter through the top - orange arrows (under the cowling).
I think it would be a simple fix with parts I already have.