The longest cycle and relation between the generating elements of a Cayley graph

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Let $G$ be a finite group and $S$ be a subset of $G$. We define the Cayley graph of $G$ with respect to $S$ as follows, provided that $1 {\not\in} S$ and $S$ is inverse closed.

Definition: The Cayley graph of $G$ with respect to $S$, $Cay(G,S)$ is the graph whose vertices are the elements of $G$ and $g$ is adjacent to $gs$ for all $g \in G, \, s \in S$.

image 1

I have written down several cycles in the above Cayley graph as follows.

image 2 image 3

((1), (2), (3) cycles sketched in red, green and pink respectively).

All (1), (2), (3) shows relationships between the elements $g_1$ and $g_2$.

(3) is the relationship given by a longest cycle. However, the same relationship is given by equation (2) which is not related to a longest cycle. When considering (3), when thinking about the powers of $g_1$ and $g_2$, it seems as if the powers satisfy,

$3 \equiv 0 (mod 3) \rightarrow (i)$

$0 \equiv 0 (mod 5) \rightarrow (ii)$

and when considering (4), it seems to satisfy,

$0 \equiv 0 (mod 3) \rightarrow (iii)$

$5 \equiv 0 (mod 5) \rightarrow (iv)$

So, in a situation where $|g_1|=p$ and $|g_2|=q$ where $p, q$ are distinct primes and $g_1^m g_2^n =e$, will it satisfy, $m \equiv 0 (mod p)$ and $n \equiv 0 (mod q)$?

The L.H.S. of both $(i), (ii)$ have got a value congruent to the equivalence class $0$ and in $(iii), (iv)$ also, it is the same. One has got the value equal to $p$ or $q$ in the modulus and the other always $0$. Is it a characteristic occupied by the longest cycle? I mean can I explain that it is due to the longest cycle?

If so, whenever I have a relation $m \equiv 0 (mod p)$ and $n \equiv 0 (mod q)$, can I conclude that the relation corresponding to a longest cycle is given by the solutions either,

$(m=0,n=q)$ or $(m=p, n=0)$?

Is there a way to mention a specific characteristic occupied by the longest cycle to these powers of the generating elements?