list manipulation – creation of sublists by rules

I have a list consisting mixed strings and numbers:

lis = {{{"a",1,2," 34 "},{"b",5,6," cc "}},{{"d",7," ee"},{"f",9,"1"}}

I would like to produce two sublists res1 and res2 as follows:

res1 consists of the first element of each sublist:

res1 = {"a","b","d","f"}

res2 is either:
1) the last element of each sublist IF it consists only of string representations of numbers (no letters) and 2) if it doesn’t, then the second element will be the element immediately preceding the last element in the sublist as follows:

res2 = {" 34 ",6,7,"1"}

Thanks for suggestions.