I was having the same issue and working with my Linux admin figured the issue and resolved. RHEL 7/8 work just fine but seem as pointed out there is a change in cryto policy in REHL9.
My admin ran "update-crypto-policies --set LEGACY" to set to legacy ssl2 on the RHEL9 VM and the ssh is working again. The newer RHEL9 default policy uses ssl3 and it seems vRA/vRO is not using this updated ssl3 hence the issue connecting to RHEL9.
Note Use "update-crypto-policies --show" shows the current policy which will be DEFAULT