Did you inspect the engine for visible damage?

T- chain will sometimes knock a hole in the valve cover.

Perhaps an ancillary component failed- belt or pulley?

__________________
'90 300SE 298k
-300K and it gets put into retirement.
'80 300D 255k Purchased new by family in 1980.

Had a:
1973 220 (gas)
1980 300SD
1992 400E