Seeding failure,head scratcher

Neighbor seeded 2 fields with Alfalfa and a grass mix.
One field was beans last yr and other corn.
Seed was mixed with fertilizer and spread with airflow and rolled in.
He got a good stand and it was 3-4” tall and nice and green then leaves turned tan/brown and dried up.
Wind storm came threw and blew all the leaves off.Stems left standing.
The grass that was seeded was a lot thinner then should of been.
They have gone over all chemical application records and shouldn’t be issue with any carryover.Also the 2 fields had totally different chems last yr.
The dieing off of the plants was even across the entire field was no different in low ground or higher ground.So that pretty much rules out plant diseases.
I think it could be a screw up at fertilizer plant and to me the only thing that makes any sense.They said no way it could happen.
They looked into testing soil for chems but you have to test for specific chemical groups and no way of knowing what to test for.Testing for everything possible would cost over $1000.IIRC about $200 per test.
They want to reseed it.
They dug it up because waterhemp was coming in spots.
Sure seems risky to me to seed it again but that’s what they want to do.
Sure is a head scratcher.

Seeding failure,head scratcher