I went out of town for 2 weeks, leaving my 5 Japanese Maple Bonsai (roughly 13 years old) and a Fukien Tea in the care of a neighbor and came back to find the leaves were dead and brown. However there appears to be green when scratching most branches so I am hopeful for next year. Several need repotting, should I do that now or wait until early spring. Any other suggestions?

Absolutely NO WAY re pot now, then you will know in spring if any are alive and not your fault. If you re pot them now it will probably be the death knell for them.