no mate they don't crush,, I use them on high pressure hose's and hydraulic fittings all the time,, they never leak and can stand huge amounts of pressure,,,,
I know this is highly unlikely but I have seen this before,, where the oil feed line as sprunk a tiny pin hole on the weld with the eye end,,
all I can recommend is with out taking the oil feed pipe off, ( NIGHTMARE JOB ) make sure you have clean surface's when re-fitting new seals and you don't need to tighten it dog tight,, just nip it up and then a little tighten,,,,
was it a new, recon or 2nd turbo you fitted??
let us know how you get on with pal