How to troubleshoot unable to PING remove network over VPN

Hi,
We have site to site vpn with a company who manages our in-house software. They have allowed 5 IP addresses to be able to PING & connect to their SQL server (port 1433) on their end over the vpn tunnel. Their SQL server IP is 192.168.20.10.

We use Cisco ASA.

I have added 4 IP to the VPN connection profiles.

object-group network DM_INLINE_NETWORK_10

network-object object 172.24.12.11

network-object object 172.24.12.12

network-object object 172.24.12.13

network-object object 172.24.12.14

object network ExtDev-Subnet-1

subnet 192.168.20.0 255.255.255.0

access-list outside_cryptomap_1 extended permit ip object-group DM_INLINE_NETWORK_10 object ExtDev-Subnet-1

nat (inside,outside) source static DM_INLINE_NETWORK_10 DM_INLINE_NETWORK_10 destination static ExtDev-Subnet-1 ExtDev-Subnet-1 no-proxy-arp route-lookup

The problem is one of our host 172.24.12.12 cannot ping or telnet 192.168.20.10 or their gateway 192.168.20.1. Rest 3 hosts has no problem ping/telnet.

Local Firewall on 172.24.12.12 has been disabled. As a test I have temporarily assigned 172.24.12.12 to a Windows 10 client which also couldn't ping/telnet.

They (192.168.20.0/24) have no problem ping our 4 servers. I have asked them to check their firewall config and they said all looks good on their end and they think its something on our end.

How do I troubleshoot this ? Any help on this will be much appreciated, thank you.