Inconsistent TSS plot generation

[WilliamKMLai]

Example PEGR ID: 36585

Payload from Galaxy:
pegr_url:
https://vesta.cac.cornell.edu/pegr/api/stats

payload:
{"genome": "hg19", "historyId": "bf3ba30a5d50ee8a", "parameters": {"input2X__identifier__": "/cephfs/galaxy_data/datasets/c/0/8/dataset_c0819512-9d3a-481c-8bb6-2a9c5b0756eb.dat", "title": "TSS", "xlabel": "TSS"}, "run": 678, "sample": 36583, "statsToolId": "tss_pileup_frequency_output_stats", "toolCategory": "output_tagPileup", "toolStderr": "", "toolId": "scriptmanager_tag-pileup", "userEmail": "wkl29@cornell.edu", "workflowId": "f501013168d48b79", "workflowStepId": null, "statistics": [{}, {}, {}], "datasets": [{"id": "4631271a9d40c3fc", "type": "tabular", "uri": "https://hyperion.cac.cornell.edu/datasets/4631271a9d40c3fc/display?preview=False"}, {"id": "f181f3a01995a45a", "type": "tabular", "uri": "https://hyperion.cac.cornell.edu/datasets/f181f3a01995a45a/display?preview=False"}, {"id": "d46e6602a7a79b60", "type": "tabular", "uri": "https://hyperion.cac.cornell.edu/datasets/d46e6602a7a79b60/display?preview=False"}], "history_url": "https://hyperion.cac.cornell.edu/histories/view?id=bf3ba30a5d50ee8a"}

response:
{'message': 'Success!', 'response_code': '200'}