Honestly for smaller groups, nows the time to expand your forces and invite more people. Odds are if they do it like ixali quest it might just be any 4 lv 50+ crafter or rather whatever the lv of crafter items needed.

There are two ways it could work.

If the items are smith/carp/carp/leather then you might need 1 smith, 2 carp, 1 leather to do that synth. Or they might just allow you to use any 4 crafters as long as all the items are in place much like ixali let you synth on any craft regardless of what you are making.