ohpoppy

My 02 9-5 Linear
81,000 miles just bought it 1 month ago
1500 miles ago switched to synthetic oil
1000 miles ago oil pressure light went on briefly and I dropped pan and cleaned screen
now turbo blew and light went on.. stopped engine immediately..lost oil
I ordered a turbo insert and will install it when it comes, old one is out and wiped out.
did compression test.. 180 on all

questions
1 is catalytic convertor ok even though 3 quarts of synthetic oil likely passed through it
2. should I check the oil screen again now or how many miles from now..or never
3. the turbo center section is a chinese one.. anything I should know about installing it
4. How will this cheaper one hold up compared to the factory unit
5. I expect much oil was forced through bad bearings in the old turbo.. should I expect
that any gritty matter or sludge residue has been discharged so the new turbo will not fail
6. should I drain the little oil in it and change filter.
I am out of town and doing this from a motel parking lot since the dealer wants 1900 to do it so any unnec work I would like to avoid. Have 900 miles to drive home with it. thanks, Bob