Excel formula to find value in multiple dynamic arrays

[radub]

Good evening,
i've been struggling to find a solution to this, but no solution so far :|
Is there a chance I can use Excel 365 formula to find a value in multiple dynamic arrays, and return the array name?
Something like this :

dARR1: one, two , three
dARR2: two, three, five, eight, dARR1
dARR3: two, six, dARR2
dARR4: eight, nine, three, one, two, dARR3
dARR5: two, five, one, six

result:
six: belongs to dARR3, dARR4, dARR5

Thank you,

 

[radub]

Based on your example with names does this help??

Book1
	A	B
1	initial data
2	groupName	Members
3	group1	John, Anne, Marie
4	group2	Josh,Alex,John,Anne,Marie
5	group3	Adele,Ema
6	group4	Keith,Ed,Scott,Josh,Alex,John,Anne,Marie
7	group5	Valerie,Luci,Keith,Ed,Scott,Josh,Alex,John,Anne,Marie
8
9
10	RESULT
11	Person	Group(s)
12	Ema	group3
13	Alex	group2:group4:group5
14	John	group1:group2:group4:group5
Sheet3

Cell Formulas
Range	Formula
B12:B14	B12	=TEXTJOIN(":",,FILTER($A$3:$A$7,REGEXTEST($B$3:$B$7,A12,1)))

Thank you so much AhoyNC.
I never used the new REGEX functions but good to see them at work. I guess I need the djclements's work for flatening the nested groups.
Thank you once again