The Triton V10 is old school and a Euro additive package is more robust than your bog standard API SP one, so that definitely would not have caused an issue.
He'd have had to use something that:
- Didn't have an additive package (so,
like something on the PQIA watch list)
- Was so inappropriate in viscosity that it didn't pump
or it was insanely thin, like 0W-8, and took out the bearings. If it was the former, well, he would have had a hell of a time pouring it in the engine, and if it's the latter, he's a moron. Scratch that, in either instance, he'd be a moron.