While we always require video evidence for all teamkill reports to ensure that it was intentional and not forced upon towards the other player, I am going to make an exception to this report. They have a prior record of rule violations, and this session in particular concerns me greatly given that it reflects the same timeframe that you submitted this report.
I'm going to issue a ban for the time being so they can come appeal and we can discuss things further with them.
Please make sure that you are supplying video evidence for teamkill reports in the future as 99.99% of the time screenshots will not suffice.