Hopefully the garage will use the proper VW sump sealant (very sparingly), or Dirko equivalent from Amazon etc. A lot of places just spread generic silicon on cake frosting, and it falls off inside and clogs the pick-up, therefore defeating the purpose of dropping the sump in the first place!
I did mine last summer and found said chunks of black silicon at the bottom of the sump.
The other benefit of the proper sealant is it dries in 20 minutes, so the car will out the door quicker. Silicon takes hours.