I'm sure someone has done this, he has very high WE, will it work? (DIII)

You can try - sometimes works, often wont

best to buy it beforehand…. definitely works on jucos.  I've never tried it on a transfer, but I think it would work just the same.  you just want to combine a certain amount of hv and other effort so he doesn't stop considering you.  I usually do overkill, like 2-3 hv, 3-4 sv (since that effort can't be denied), and good amount of calls and letters.

Check his history tab first-if he's already been redshirted (which is possible since he's a transfer) I'm assuming it won't let you R/S him again.