accessing a server without static ip

[BardiaMGTGC]

i have 3 servers 

first one with network access(lets call it S1) then second one with network access (lets call it S2) they both have public static ips these servers are in 2 different datacenters

my third server is in the same datacenter of S2 but doesnt have a static ip it can be accessed by S2 locally 

is there anyway i can access my third server from S1 without sshing to S2 then sshing to the third server? (they are all linux)

also S3 has no network access i use proxychains with ss-local to install packages etc