"I don't know why filling the tank would cause the check valve to malfunction,"

My check valve thought was not based on the act of filling up, but on the assumption that the engine being off (while filling up) was long enough to allow "heat soak" from a warm/hot (?) motor to boil the fuel in the injector fuel line, causing fuel bubbles to form a "vapor lock" which blocked the fuel flow.

A working check valve would prevent the vapor lock bubble from forming by maintaining in some residual fuel pressure while the motor was off during the fill up time.

In your case, I'm guessing that the "5 minutes" of cranking you mention was long enough for the vapor lock to dissipate, restoring normal operation. I would try a fuel pressure test to monitor both running and residual pressure under the conditions you've described.

An inline gauge tee'd in at the fuel rail inlet could be left in place for a quick check at the next fill up.
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Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.